Abstrict A crusher bucket includes a bucket body (70) and a crushing lid
(76) provided on the bucket body. The crushing lid is capable of
being opened and closed relative to the bucket body. A material
feed rate adjusting mechanism is provided on the bucket body (70)
and/or the crushing lid (76) to allow raw material scooped up into
the bucket body (70) to be fed into a crushing chamber (70a) in
a predetermined amount at a time. Hammers (74) are disposed on the
outer periphery of a rotor driven rotationally by a power drive
device to strike and break the raw material fed into the crushing
chamber (70a). A repulsion plate (77) is provided on the crushing
lid (76) to collide with the raw material struck by the hammers
(74). The material feed rate adjusting mechanism is preferably a
weir (72) provided on the bottom wall of the bucket body (70).
Claims What is claimed is:
1. A crusher bucket comprising: a bucket body (7 70); a crushing
lid (12 76) provided on said bucket body, said crushing lid being
capable of being opened and closed relative to said bucket body;
a material feed rate adjusting mechanism provided on at least one
of said bucket body (7 70) and said crushing lid (12 76) to allow
raw material scooped up into said bucket body (7 70) to be fed
into a crushing chamber (7a, 70a) in a predetermined amount at a
time; hammers (11 45 74) disposed on an outer periphery of a rotor
driven rotationally by a power drive device to strike and break
said raw material fed into said crushing chamber (7a, 70a); and
a repulsion plate (16 77) provided on said crushing lid (12 76)
to collide with said raw material struck by said hammers (11 45
74).
2. A crusher bucket according to claim 1 wherein said material
feed rate adjusting mechanism is a weir (72) provided on a bottom
wall (71) of said bucket body (70).
3. A crusher bucket according to claim 1 or 2 wherein each of
said hammers (11 45 74) has an opening (31) open outward and a
cut portion (30) communicating with said opening (31), said cut
portion being formed with a bearing (29) that supports said hammer
(11 45 74) when said rotor rotates; said crusher bucket further
comprising: a hammer pivot shaft (24) inserted into said bearing
(29) through said opening (31) during assembly process to pivotably
support said hammer (11 45 74); a hammer retainer (35 55 65)
inserted into said opening (31) and secured to said hammer (11
45 74); and a securing member (43 60) for securing said hammer
(11 45 74) and said hammer retainer (35 55 65) to each other.
4. A crusher bucket according to claim 3 further comprising: a
mutually connecting mechanism whereby said hammer (11 45 74) and
said hammer retainer (35 55 65) are detachably connected to each
other; said mutually connecting mechanism including: first engaging
elements (32) formed at opposite ends of said opening (31); and
second engaging elements (38) to be detachably engaged with said
first engaging elements (32), said second engaging elements (38)
being formed on said hammer retainer (35).
5. A crusher bucket according to claim 3 wherein said hammer retainer
comprises two hammer retainer members (55 65) provided facing each
other; said crusher bucket further comprising: a mutually connecting
mechanism whereby said hammer (11 45 74) and said hammer retainer
(35 55 65) are detachably connected to each other; said mutually
connecting mechanism including: first engaging elements (50) formed
at two positions in said cut portion (30) in a radial direction
of said bearing (29); and second engagement elements (58 68) to
be detachably engaged with said first engaging elements (50), said
second engaging elements (58 68) being formed on said hammer retainer
members (55 65), respectively.
Description BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a crusher bucket with a
crushing lid for recycling lumps of asphalt, scraps of concrete,
etc. More particularly, the present invention relates to a crusher
bucket attached to the distal end of an arm of a civil engineering
machine and having the function of crushing raw materials. Even
more particularly, the present invention pertains to a crusher bucket
with a crushing lid improved in maintainability and productivity.
[0003] 2. Discussion of Related Art
[0004] A civil engineering machine that is generally called "impact
crusher" crushes and grinds material to be crushed (raw material)
such as industrial waste, i.e. concrete scraps, asphalt paving mixture,
aggregate for civil engineering and construction applications, or
crushed stone. The crushed materials are reused as recycling materials.
The impact crusher has a rotor with a horizontal axis in a casing.
The rotor has a plurality of hammers radially arranged thereon.
Material to be crushed is loaded into the crusher with the rotor
rotating. The material is impacted between the rotor and a repulsion
plate secured to the casing inner surface, thereby being crushed.
The hammers mounted on the rotor are always in direct contact with
the raw material under impact force. Therefore, the distal end portions
of the hammers wear out as the service time of the crusher elapses.
[0005] Generally, the distal end portions of the hammers become
worn out to a considerable extent when a predetermined time has
elapsed. As a result, the crushing efficiency degrades markedly.
Meanwhile, if a large amount of material to be crushed is fed at
a time into the crushing chamber in which the hammers are rotating,
the material is likely to be caught between the casing body (the
bucket body) and the hammers, causing an interruption of the crushing
operation. If the material to be crushed gets caught in this way,
it becomes necessary to perform an operation of disassembling the
hammers to release and remove the caught material. Regarding the
hammer mounting structure, the present applicant proposed a technique
whereby after a hammer has been inserted into a cut portion of a
rotor body, an engaging projection is fitted into an engaging hole
formed in a retaining block to support the hammer, and the retaining
block is supported between support members, thereby securing the
hammer [see Japanese Utility Model Unexamined Publication (KOKAI)
No. Hei 4-45547 and Japanese Patent Unexamined Publication (KOKAI)
No. 2001-190972].
[0006] The hammers of stationary impact crushers are stationary.
There is, however, known a small-sized crusher in which hammers
are pivotably supported on pivot shafts to crush raw material by
the pivotal motion of the hammers. The pivoted hammers can be used
also as members for mixing clayish soil with air or a soil conditioner,
e.g. a stabilizer, and stirring the mixture. Replacement of the
hammers is generally made by removing the pivot shafts pivotably
supporting the hammers.
[0007] Conventionally, scrap materials such as asphalt lumps are
reprocessed at a site where a recycling plant is installed. This
method requires a great deal of energy, time and cost to transport
scrap materials from the site where they are generated to the reprocessing
site. Therefore, there have recently been proposed methods wherein
a small amount of recyclable material is directly reprocessed at
a site where it is generated. Among these are methods wherein recyclable
material is reprocessed in a bucket of a civil engineering machine.
Many proposals have been made regarding the method and structure
of crushing in the crusher bucket [for example, see Japanese Patent
Unexamined Publication (KOKAI) Nos. Hei 9-88355 Hei 10-30247 and
2001-113198].
[0008] When material to be crushed gets caught between the crusher
hammers and the casing body, an operation of removing and remounting
the hammers and so forth has to be performed to release and remove
the caught material. When becoming worn or damaged, the hammers
need to be replaced with new ones. The hammer replacing operation
plus the hammer removing and remounting operation increases downtime
for maintenance and degrades productivity. Further, impact hammers
require the hammer replacing operation to be carried out relatively
frequently. Because these hammers are small in size, the space for
the replacing operation is narrow and it is difficult to perform
the operation. Therefore, the hammer removing or replacing operation
has to be done as efficiently as possible. In the case of pivoted
impact hammers, in particular, the pivot shafts need to be removed
in order to replace the hammers, and it is necessary to temporarily
remove another hammer that is provided on the same pivot shaft as
the one to be replaced and that need not be replaced.
[0009] Thus, there has been a demand for development of a crusher
bucket with a crushing lid improved in maintainability and productivity.
More specifically, it has been demanded to provide a crusher bucket
arranged so that material to be crushed will not easily be caught
between the bucket body and the hammers, etc., thereby minimizing
the likelihood of occurrence of an event requiring the material
removing operation, and in the event that material to be crushed
gets caught, the hammer removing and remounting operation can be
readily performed to remove the caught material.
SUMMARY OF THE INVENTION
[0010] The present invention was made to solve the above-described
problems and to attain the following objects.
[0011] An object of the present invention is to provide a crusher
bucket with a crushing lid that is arranged so that raw material
(material to be crushed) is fed into the crushing chamber in a predetermined
amount at a time, thereby making it unlikely that the raw material
will be caught between the bucket body and the hammers, etc.
[0012] Another object of the present invention is to provide a
crusher bucket with a crushing lid that facilitates the hammer removing
and remounting or replacing operations to improve maintainability
and productivity.
[0013] To attain the above-described objects, according to a first
feature thereof, the present invention provides a crusher bucket
including a bucket body and a crushing lid provided on the bucket
body. The crushing lid is capable of being opened and closed relative
to the bucket body. A material feed rate adjusting mechanism is
provided on the bucket body and/or the crushing lid to allow raw
material scooped up into the bucket body to be fed into a crushing
chamber in a predetermined amount at a time. Hammers are disposed
on the outer periphery of a rotor driven rotationally by a power
drive device to strike and break the raw material fed into the crushing
chamber. A repulsion plate is provided on the crushing lid to collide
with the raw material struck by the hammers.
[0014] According to a second feature of the present invention,
the material feed rate adjusting mechanism of the crusher bucket
according to the first feature of the present invention is a weir
provided on the bottom wall of the bucket body.
[0015] According to a third feature of the present invention, each
of the hammers in the crusher bucket according to the first or second
feature of the present invention has an opening open outward and
a cut portion communicating with the opening. The cut portion is
formed with a bearing that supports the hammer when the rotor rotates.
A hammer pivot shaft is inserted into the bearing through the opening
during assembly process to pivotably support the hammer. A hammer
retainer is inserted into the opening and secured to the hammer.
The crusher bucket further includes a securing member for securing
the hammer and the hammer retainer to each other.
[0016] According to a fourth feature of the present invention,
the crusher bucket according to the third feature of the present
invention further includes a mutually connecting mechanism whereby
the hammer and the hammer retainer are detachably connected to each
other. The mutually connecting mechanism includes first engaging
elements formed at the opposite ends of the opening of the hammer.
Second engaging elements to be detachably engaged with the first
engaging elements are formed on the hammer retainer.
[0017] According to a fifth feature of the present invention, the
hammer retainer in the crusher bucket according to the third feature
of the present invention has two hammer retainer members provided
facing each other. The crusher bucket further includes a mutually
connecting mechanism whereby the hammer and the hammer retainer
are detachably connected to each other. The mutually connecting
mechanism includes first engaging elements formed at two positions
in the cut portion of the hammer in the radial direction of the
bearing. Second engagement elements to be detachably engaged with
the first engaging elements are formed on the hammer retainer members,
respectively.
[0018] The crusher bucket with a crushing lid according to the
present invention has a material feed rate adjusting mechanism,
e.g. a weir, provided on the bottom wall of the bucket body. With
this arrangement, raw material can be fed into the crushing chamber
in a predetermined amount at a time. Therefore, there is substantially
no possibility of raw material getting caught between the bucket
body and the hammers, etc. Accordingly, there is a marked reduction
in the incidence of an event requiring an operation for removing
caught raw material or the like. In addition, it is possible to
readily remove and remount a pivoted impact hammer without the need
to remove the pivot shaft supporting the hammer. In other words,
it is possible to improve the crusher bucket in maintainability
in the real sense of the term.
[0019] In addition, the amount of time required for maintenance
of the crusher other than the time for crushing operation, i.e.
downtime, is minimized, and hence the productivity of the crusher
is improved.
[0020] The above and other objects, features and advantages of
the present invention will become more apparent from the following
description of the preferred embodiments thereof, taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a side view of a crusher bucket with a crushing
lid according to a first embodiment of the present invention.
[0022] FIG. 2 is a front view of the crusher bucket according to
the first embodiment of the present invention.
[0023] FIG. 3 is a sectional view taken along the line X-X in FIG.
2.
[0024] FIG. 4 is a side view showing the crushing lid provided
with repulsion plate liners and a first scatter preventing member.
[0025] FIG. 5 is a side view showing the crushing lid provided
with the repulsion plate liners and a second scatter preventing
member.
[0026] FIG. 6 is a fragmentary view showing the arrangement of
the crushing lid equipped with the first scatter preventing member.
[0027] FIGS. 7(a) and 7(b) are a front view and a right-hand side
view, respectively, showing a hammer used in a first hammer removably
securing mechanism.
[0028] FIGS. 8(a) and 8(b) are a plan view and a front view, respectively,
showing a hammer retainer used in the first hammer removably securing
mechanism.
[0029] FIG. 9 is an explanatory view showing an assembly procedure
performed to mount a hammer on a hammer pivot shaft with the first
hammer removably securing mechanism.
[0030] FIG. 10 is a plan view of FIG. 9.
[0031] FIG. 11 is an explanatory view showing a state where the
process of mounting the hammer on the hammer pivot shaft with the
first hammer removably securing mechanism has been completed.
[0032] FIGS. 12(a) and 12(b) are a front view and a right-hand
side view, respectively, showing a hammer used in a second hammer
removably securing mechanism.
[0033] FIGS. 13(a) and 13(b) are a front view and a right-hand
side view, respectively, showing a first hammer retainer member
of the second hammer removably securing mechanism.
[0034] FIGS. 13(c) and 13(d) are a front view and a left-hand side
view, respectively, showing a second hammer retainer member of the
second hammer removably securing mechanism.
[0035] FIG. 14 is an explanatory view showing an assembly procedure
performed to mount a hammer on a hammer pivot shaft with the second
hammer removably securing mechanism.
[0036] FIG. 15 is a plan view of FIG. 14.
[0037] FIG. 16 is an explanatory view showing a state where the
process of mounting the hammer on the hammer pivot shaft with the
second hammer removably securing mechanism has been completed.
[0038] FIG. 17 is a side view of a crusher bucket with a crushing
lid according to a second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] Embodiments of the present invention will be described below
with reference to the accompanying drawings.
A Crusher Bucket with a Crushing Lid According to a First Embodiment
[0040] A first embodiment of the crusher bucket according to the
present invention will be described below in detail with reference
to FIGS. 1 to 6. FIG. 1 is a side view of a crusher bucket with
a crushing lid according to the present invention. FIG. 2 is a front
view of the crusher bucket. FIG. 3 is a sectional side view taken
along the line X-X in FIG. 2 which corresponds to FIG. 1. FIG.
4 is a side view of the crushing lid in a state where it has repulsion
plate liners attached to the inner wall thereof and a first scatter
preventing member attached to one side wall thereof. FIG. 5 is a
side view of the crushing lid in a state where it has repulsion
plate liners attached to the inner wall thereof and a second scatter
preventing member attached to the distal end thereof. FIG. 6 is
a fragmentary view showing the arrangement of the crushing lid equipped
with the first scatter preventing member.
[0041] A backhoe to which the crusher bucket according to the present
invention is applied is a civil engineering machine of the same
kind as a power shovel and is a publicly known excavator. Therefore,
a detailed description of the backhoe is omitted. The backhoe is
generally used for excavation of earth below the machine to perform
an operation such as digging a hole, a trench, etc.
[0042] An arm 1 has a bucket 3 pivotably provided at the distal
end thereof through a pivot shaft 2. The arm 1 is provided with
a bucket cylinder (not shown). The distal end of a piston rod of
the bucket cylinder is relatively rotatably connected to one end
of a connecting member 4 through a shaft 5. The other end of the
connecting member 4 is relatively rotatably attached to a bucket
body 7 through a shaft 6. That is, when the piston rod is advanced
or retracted by driving force of the bucket cylinder, the bucket
body 7 pivots about the pivot shaft 2.
[0043] The bucket 3 is movable to any position within a given turning
range by the operation of the backhoe body and can also change its
direction. The bucket body 7 of the bucket 3 is used to scoop up
raw material (material to be crushed), e.g. lumps of asphalt or
concrete, and to load them into the inside of the bucket body 7
to crush and to transport the crushed material.
[0044] The crusher bucket will be described as a bucket that has
in its bottom a discharge opening for discharging pieces of raw
material crushed to a predetermined size. In addition, the bucket
has a mesh grate attached to the discharge opening to adjust the
particle size, and further has a rotor that crushes loaded raw material
by impacting it with hammers serving as breaking teeth, as will
be explained later. The top of the bucket body 7 of the bucket 3
is provided with an opening 8 for loading scrap or other raw material
into the bucket body 7. A rotor shaft 9 is rotatably provided on
the bucket body 7 and driven by a rotor driving device 10 disposed
outside the bucket body 7.
[0045] The rotor shaft 9 has a plurality (8 in the first embodiment)
of disks 23 disposed thereon at predetermined regular spacings.
The rotor shaft 9 and the disks 23 in combination constitute a rotor.
Headed hammer pivot shafts 24 are provided to extend between each
pair of adjacent disks 23 at respective positions on the outer peripheral
portion of each disk 23 angularly spaced from each other by 90.degree..
The other ends of the hammer pivot shafts 24 are threaded and have
respective nuts screwed onto them. Each hammer pivot shaft 24 has
two hammers 11 pivotably provided thereon. The details of the connecting
mechanism for the hammer pivot shafts 24 and the hammers 11 will
be described later.
[0046] Thus, the rotor shaft 9 has a plurality of hammers 11 pivotably
secured thereto. When the rotor shaft 9 rotates, the hammers 11
repetitively strike (beat) and crush raw material. The hammers 11
are mounted in such a manner as to be replaceable when becoming
worn or damaged, as will be described later. The hammers 11 are
formed from a rigid and wear-resistant metallic material. Thus,
the hammers 11 are individually replaceable with new ones when their
striking surfaces have become worn or damaged.
[0047] When the crushing lid 12 is closed or half open, the inside
of the bucket body 7 defines a crushing chamber 7a that is used
to crush raw material loaded thereinto (see FIG. 3). The inner wall
of the crushing chamber 7a is covered with a rigid material. A crushing
lid 12 is provided on the top of the bucket body 7. A lid opening-closing
cylinder (opening-closing device) 13 is pivotably provided through
a shaft 13a on the bucket body 7 to allow the crushing lid 12 to
be selectively opened or closed.
[0048] During crushing of raw material in the crushing chamber
7a, the crushing lid 12 is closed to prevent scattering of pieces
of crushed material from the opening 8 to the outside of the bucket
body 7. The distal end of a piston rod 13b of the lid opening-closing
cylinder 13 is connected to one end of the crushing lid 12 through
a lever 14 and a shaft 15. Consequently, when the lid opening-closing
cylinder 13 is driven, the crushing lid 12 pivots about the shaft
15 provided on the bucket body 7. Thus, the crushing lid 12 is selectively
opened or closed in response to the operation of the cylinder 13.
[0049] The lever 14 is secured to the shaft 15 and the distal
end of the piston rod 13b is connected to the lever 14. In response
to the advancing or retracting movement of the piston rod 13b, the
crushing lid 12 is closed or opened through the lever 14 and the
shaft 15. In FIG. 3 the crushing lid 12 in its closed position
is shown by the solid lines. The crushing lid 12 in its open position
is shown by the chain double-dashed lines. Although the opening-closing
device has been described as the lid opening-closing cylinder 13
it may be other actuator, for example, a hydraulic motor, or an
electric motor used in combination with a thread member.
[0050] The crushing lid 12 has a repulsion plate liner 16 for crushing
secured to the inner wall thereof. The repulsion plate liner 16
is formed in an approximately V-shape in section such that the center
thereof projects radially inward of the crushing lid 12. The crushing
lid 12 in the first embodiment has a plurality of repulsion plate
liners 16 secured to the inner wall thereof. The repulsion plate
liners 16 are formed from a rigid material and individually replaceable
with new ones when they have become worn or damaged by a crushing
operation.
[0051] Because the repulsion plate liners 16 are formed in an approximately
V-shape in section, raw material can be readily crushed by colliding
against the V-shaped projecting portions of the repulsion plate
liners 16. Thus, the crushing effect is further improved. The crushing
lid 12 has an approximately circular arc shape so that when closed,
the crushing lid 12 extends in conformity to the orbit of the rotating
hammers 11. When closed, the crushing lid 12 cooperates with the
bucket body 7 to define a crushing chamber 7a in which raw material
is crushed by the rotation of the hammers 11 of the rotor.
[0052] Next, the scatter preventing structure will be described.
The crushing lid 12 according to the first embodiment is provided
with scatter preventing members at widthwise and distal end portions
thereof. Regarding the widthwise portion, as shown in FIG. 4 a
first scatter preventing member 17 is secured to each side surface
of the crushing lid 12 in a circular arc shape along the lid configuration.
The configuration of the first scatter preventing member 17 corresponds
to the inner wall of the bucket body 7.
[0053] The first scatter preventing member 17 is provided on a
reinforcing wall 12a of the crushing lid 12. An adequate gap is
provided between the reinforcing wall 12a and the inner wall of
the bucket body 7. The first scatter preventing member 17 is provided
to fill the gap. The first scatter preventing member 17 is secured
to the reinforcing wall 12a of the crushing lid 12 by welding or
using screws. The first scatter preventing member 17 secured to
the reinforcing wall 12a is in line contact with the inner wall
of the bucket body 7. Alternatively, the first scatter preventing
member 17 faces the inner wall of the bucket body 7 across a gap
of about 1 to 3 mm. The gap is set so that there is no interference
with the lid opening-closing operation.
[0054] The first scatter preventing member 17 has a circular sectional
configuration. FIG. 6 shows a round rod material 17a bent in a circular
arc shape and secured to the reinforcing wall 12a by welding. Further,
as shown in FIG. 5 a second scatter preventing member 18 is provided
on the distal end portion of the crushing lid 12.
[0055] The second scatter preventing member 18 has a closure member
18a coming into direct contact with the bottom wall of the bucket
body 7. The closure member 18a is urged by a spring member 18b and
retained by a plate 18c so that the closure member 18a retractably
projects from the distal end of the crushing lid 12. The second
scatter preventing member 18 extends over the entire width of the
crushing lid 12. When the crushing lid 12 is closed, the distal
end of the closure member 18a comes in close contact with the bottom
wall of the bucket body 7 so that the crushing chamber 7a is closed.
[0056] A rotor driving device 10 for driving the rotor shaft 9
is provided on a side wall of the bucket body 7. The rotor driving
device 10 has a hydraulic motor to rotate the rotor shaft 9 through
a V-belt 10a. In this embodiment, two rotor driving devices 10 with
the same arrangement are provided on both sides of the bucket body
7. Provision of two identical rotor driving devices 10 on both sides
of the bucket body 7 improves the rotational balance of the rotor
shaft 9 and hence allows the rotor shaft 9 to rotate smoothly. Moreover,
an increased torque can be obtained.
[0057] Further, because the rotor shaft 9 is driven through a V-belt
10a, vibrations transmitted to the bucket body 7 and noise generated
owing to the drive of the rotor shaft 9 are reduced in comparison
to the type of driving system in which the rotor driving device
is connected directly to the rotor shaft 9. Further, the V-belt
10a absorbs shock applied to the rotor driving system owing to rapid
rotation, a forward-backward switching operation, or sudden overloading
during crushing. Therefore, damage to the power transmission parts
or the motor can be prevented. The rotor driving device 10 does
not limit the rotational direction of the rotor shaft 9 but allows
selection between forward and backward rotations by a switching
operation. As a result, crushing of raw material is accelerated,
and the crushing efficiency increases. The rotor driving device
10 is, although not shown in detail, supported by a housing 19 that
is secured to one side wall of the bucket body 7. The driving system
is connected to the rotor shaft 9 in the bucket body 7.
[0058] Meanwhile, pieces of raw material crushed to a predetermined
size drop to the bottom of the bucket body 7. The bottom of the
bucket body 7 is provided with three discharge openings 20. The
crushed or ground materials are discharged from the discharge openings
20. Usually, the discharge openings 20b and 20c in the side wall
of the bucket body 7 are covered with a cover 21 with a view to
enhancing the crushing effect. Pieces of crushed material are discharged
only from the discharge opening 20a that corresponds to the position
where the crushed material drops. The other discharge openings 20b
and 20c are used for maintenance and so forth.
[0059] The discharge opening 20a is provided with a grate 22 which
is a wire net of a predetermined mesh size, or a perforated steel
plate, to pass only pieces of crushed material having a predetermined
particle size. Regarding the grate 22 an appropriate mesh shape,
size and material are selected according to each particularly crushing
purpose. Consequently, pieces of crushed material capable of passing
through the discharge opening 20a are always those smaller than
a predetermined size. Coarse pieces of crushed material that cannot
pass through the discharge opening 20a are discharged from the opening
8 when the bucket 3 is turned upside down.
[0060] [First Hammer Removably Securing Mechanism]
[0061] FIGS. 7(a) and 7(b) show the details of a hammer 11. FIG.
7(a) is a front view, and FIG. 7(b) is a right-hand side view. The
hammer 11 is constructed by using a steel plate material capable
of withstanding striking. The hammer 11 has a striking end 25 formed
with two corners 26 of 90 degrees. The other end of the hammer 11
i.e. root 27 is in the shape of a semicircular arc 28. A shaft
hole 29 is formed at the center of the semicircular arc 28. A hammer
pivot shaft 24 as described above is inserted to extend through
the shaft hole 29. The shaft hole 29 forms a bearing for mounting
the hammer 11 in such a manner that the hammer 11 is pivotable about
the hammer pivot shaft 24 within a predetermined angle range.
[0062] An L-shaped cut portion 30 which is a space, is formed
contiguous with the shaft hole 29. The cut portion 30 allows the
hammer 11 to be removed from the hammer pivot shaft 24 without the
need to remove the shaft 24 when the hammer 11 that has become worn
is replaced with a new one. Dovetail grooves 32 are formed at the
opposite ends of an opening 31 of the cut portion 30. In addition,
a bolt through-hole 33 is formed in the neighborhood of the cut
portion 30. FIGS. 8(a) and 8(b) show a hammer retainer. FIG. 8(a)
is a plan view, and FIG. 8(b) is a front view. It should be noted
that the dovetail groove 32 is a groove with a dove's tail-shaped
sectional configuration, and a corresponding dovetail projection
is fitted into the groove to form an interlocking joint, which is
known as "dovetail joint".
[0063] The hammer retainer 35 is assembled into and secured to
the hammer 11 mounted on the hammer pivot shaft 24 so that the hammer
11 will not undesirably disengage from the hammer pivot shaft 24.
The hammer retainer 35 has two rectangular side plates 36 placed
parallel to each other and an insert portion 37 formed between the
side plates 36 integrally therewith. The insert portion 37 is to
be inserted into the opening 31 of the hammer 11. The insert portion
37 is formed with dovetail projections 38 complementary in dovetail
joint configuration to the dovetail grooves 32. The dovetail projections
38 are portions to be fitted into the dovetail grooves 32.
[0064] One side plate 36 is integrally provided with a bolt head
protecting member 39. The center of the bolt head protecting member
39 is provided with a hole for receiving the head of a bolt 43 (see
FIG. 10). The bolt 43 is used to secure the hammer retainer 35 to
the hammer 11. The bolt head protecting member 39 covers the outer
periphery of the head of the bolt 43 to prevent wear of the bolt
43 thereby preventing the hammer retainer 35 from falling off the
hammer 11. The side plate 36 is provided with a through-hole 40
for passing the bolt 43. A tapped hole 41 into which the bolt 43
is threaded is formed in the other side plate 36 in coaxial relation
to the through-hole 40.
[0065] FIGS. 9 to 11 are explanatory views showing an assembly
procedure performed to mount a hammer 11 on a hammer pivot shaft
24. As shown in FIG. 9 the hammer 11 is provided with a cut portion
30 with an opening 31. Therefore, the hammer pivot shaft 24 can
be inserted into the shaft hole 29 of the hammer 11 through the
opening 31. Thus, the hammer pivot shaft 24 need not be removed
from the disks 23 to mount the hammer 11.
[0066] In the state shown in FIG. 9 the hammer retainer 35 is
fitted to the hammer 11 from the direction of the arrow shown in
FIG. 10. More specifically, the insert portion 37 and the dovetail
projections 38 of the hammer retainer 35 are respectively fitted
into the opening 31 and the dovetail grooves 32 of the hammer 11.
Then, the bolt 43 is inserted into the through-hole 40 of the hammer
retainer 35 at the outer periphery of one disk 23 and from the outside
thereof. After being inserted through the through-hole 40 of the
hammer retainer 35 and the through-hole 33 of the hammer 11 the
bolt 43 is threaded into the tapped hole 41 thereby securing the
hammer 11 and the hammer retainer 35 to each other (see FIG. 11).
[0067] The other hammer 11 which pairs with the above-described
hammer 11 is fitted onto and secured to the hammer pivot shaft
24 in the same way as the above. At this time, a bolt 43 is threaded
into a tapped hole 41 of an associated hammer retainer 35 at the
outer periphery of the other disk 23 and from the outside thereof
to secure the hammer 11 and the hammer retainer 35 to each other.
In this embodiment, two hammers 11 are mounted on one hammer pivot
shaft 24 (see FIG. 2). As has been detailed above, a worn or damaged
hammer 11 can be readily replaced with a new one simply by untightening
the bolt 43 without the need to remove the hammer pivot shaft 24.
[0068] [Second Hammer Removably Securing Mechanism]
[0069] The following is a description of a second hammer removably
securing mechanism having a hammer and a hammer retainer different
in configuration from the above-described hammer 11 and hammer retainer
35. FIGS. 12(a) and 12(b) show the details of a hammer 45. FIG.
12(a) is a front view, and FIG. 12(b) is a right-hand side view.
The basic configuration of the hammer 45 is the same as that of
the above-described hammer 11. Therefore, the same structures are
denoted by using the same reference numerals, and a description
thereof is omitted. Only the features in which the hammer 45 differs
from the hammer 11 will be explained below.
[0070] The hammer 45 has dovetail grooves 50 formed at both sides
of the opening 31 in the cut portion 30. The dovetail grooves 50
are portions to be fitted with dovetail projections 58 and 68 (described
later). Insertion of the dovetail projections 58 and 68 in the dovetail
grooves 50 prevents the opening 31 from being undesirably enlarged
when the hammer 45 is subjected to centrifugal force. FIGS. 13(a),
13(b), 13(c) and 13(d) show a hammer retainer. The retainer comprises
a first hammer retainer member 55 and a second hammer retainer member
65. FIGS. 13(a) and 13(b) are a front view and a right-hand side
view, respectively, showing the first hammer retainer member 55
of the second hammer removably securing mechanism. FIGS. 13(c) and
13(d) are a front view and a left-hand side view, respectively,
showing the second hammer retainer member 65 of the second hammer
removably securing mechanism.
[0071] The first and second hammer retainer members 55 and 65 are
fitted into the hammer 45 mounted on the hammer pivot shaft 24 to
prevent the hammer 45 from falling off the shaft 24. The first hammer
retainer member 55 has a rectangular side plate 56 and an insert
portion 57 integrally formed on one side of the side plate 56. The
insert portion 57 is to be inserted into the opening 31 of the hammer
45. The insert portion 57 has dovetail projections 58 formed on
both ends thereof. The dovetail projections 58 are complementary
in dovetail joint configuration to the dovetail grooves 50 of the
hammer 45. The dovetail projections 58 are portions to be fitted
into the dovetail grooves 50. The side plate 56 is formed with two
tapped holes 59.
[0072] Similarly, the second hammer retainer member 65 has a rectangular
side plate 66 and an insert portion 67 integrally formed on one
side of the side plate 66. The insert portion 67 is to be inserted
into the opening 31 of the hammer 45 together with the insert portion
57 of the first hammer retainer member 55. The insert portion 67
has dovetail projections 68 formed on both ends thereof. The dovetail
projections 68 are complementary in dovetail joint configuration
to the dovetail grooves 50 of the hammer 45. The dovetail projections
68 are to be fitted into the dovetail grooves 50 together with
the dovetail projections 58 of the first hammer retainer member
55. The side plate 66 is formed with two bolt head protecting members
69.
[0073] FIGS. 14 to 16 are explanatory views showing an assembly
procedure performed to mount the hammer 45 on the hammer pivot shaft
24. As shown in FIG. 14 the hammer 45 is mounted on the hammer
pivot shaft 24 and in this state the first and second hammer retainer
members 55 and 65 are inserted between the disks 23 (in the arrow
direction in FIG. 15) and positioned to face each other across the
hammer 45. Then, the insert portion 57 and the dovetail projections
58 of the first hammer retainer member 55 are respectively fitted
into the opening 31 and the dovetail grooves 50 of the hammer 45.
Further, the insert portion 67 and the dovetail projections 68 of
the second hammer retainer member 65 are respectively fitted into
the opening 31 and the dovetail grooves 50 of the hammer 45.
[0074] As the result of the fitting process, the insert portion
57 and the dovetail projections 58 of the first hammer retainer
member 55 respectively face and contact the insert portion 67 and
the dovetail projections 68 of the second hammer retainer member
65. Bolts 60 are inserted into the respective through-holes of the
bolt head protecting members 69 of the second hammer retainer member
65 at the outer periphery of one disk 23 and from the outside thereof.
Then, the bolts 60 are respectively threaded into the tapped holes
59 of the first hammer retainer member 55 thereby securing the
hammer 45 and the first and second hammer retainer members 55 and
65 to each other (see FIG. 16).
Raw Material Crushing Method by the First Embodiment
[0075] The raw material crushing method carried out by the crusher
bucket 3 according to the first embodiment will be described below.
First, the crushing lid 12 of the bucket 3 is closed to begin a
crushing operation. Raw material is scooped up by the forward end
portion of the bucket body 7 in a state where the crushing lid 12
is closed. The raw material is loaded into the front portion of
the bucket body 7 that is, a space 7b defined between the bucket
body 7 and the outer wall of the crushing lid 12 when closed. Next,
the crushing lid 12 is gradually opened to feed the raw material
into the crushing chamber 7a defined between the bucket body 7 and
the inner wall of the crushing lid 12. At this time, the rotor shaft
9 is rotating. Therefore, the raw material is crushed little by
little by repetitive strikes of the hammers 11 and the effect of
striking against the repulsion plate liners 16 of the crushing lid
12. Pieces of crushed material are discharged from the discharge
opening 20a in the bottom of the bucket body 7. That is, in the
first embodiment, a material feed rate adjusting mechanism is formed
from the crushing lid 12 the cylinder 13 for opening or closing
the crushing lid 12 etc. The amount of material to be fed to the
crushing chamber 7a is adjusted by an operator adjusting the angle
of opening of the crushing lid 12.
[0076] When all the scooped raw material has been crushed, the
crushing lid 12 is closed again. Then, raw material is scooped up
by the bucket body 7 and the above-described operation is repeated.
Thus, raw material is crushed in the bucket body 7 little by little
while the crushing rate and the shape and size of crushed particles
are adjusted by adjustingly opening or closing the crushing lid
12. Accordingly, the rotating operation of the rotor shaft 9 is
stabilized. In contrast to the conventional method in which raw
material is fully loaded into the bucket body 7 and crushed at one
stroke, the first embodiment of the present invention gradually
crushes raw material and therefore can avoid an overload that might
otherwise occur during crushing. At the same time, the crusher according
to the first embodiment crushes raw material while preventing scattering
of crushed material. Therefore, it is possible to perform a crushing
operation that is favorable from the safety and environment point
of view. In addition, there is substantially no possibility that
raw material will be undesirably caught between the bucket body
7 and the hammers 11 or the rotor.
[0077] The raw material is crushed not only by impact but also
by repetitively rubbing against other raw material intermingling
therewith in the crushing chamber 7a as the rotor shaft 9 rotates.
Thus, the crusher according to this embodiment repeats the crushing
operation many times while impacting the raw material and therefore
can perform efficient crushing. Because this operation is carried
out by two rotor driving devices 10 the motor of each rotor driving
device 10 need not be large in size. Accordingly, a well-balanced
rotation can be obtained for crushing. Pieces of raw material crushed
to a particle size less than a predetermined one are discharged
from the discharge opening 20a to the outside of the bucket body
7. If raw material remains uncrushed in the bucket body 7 for some
reason, the bucket body 7 is turned upside down, and the raw material
or coarse pieces of crushed material are discharged from the opening
8.
A Crusher Bucket with a Crushing Lid According to a Second Embodiment
[0078] A second embodiment of the crusher bucket according to the
present invention will be described below.
[0079] In the following description of the second embodiment of
the crusher bucket, the same members or portions as those in the
above-described first embodiment are denoted by using the same reference
numerals, and a detailed description thereof is omitted. Only the
features in which the second embodiment differs from the first embodiment
will be explained below.
[0080] FIG. 17 is a side view of a crusher bucket that has a weir
provided on the bottom wall of the bucket body.
[0081] A bucket 80 is pivotably provided at the distal end of an
arm (not shown) through a pivot shaft 2. The arm is provided with
a bucket cylinder (not shown). The distal end of a piston rod of
the bucket cylinder is relatively rotatably connected to one end
of a connecting member (not shown) through a shaft. The other end
of the connecting member is relatively rotatably attached to a bucket
body 70 through a shaft 6. That is, when the piston rod is advanced
or retracted by driving force of the bucket cylinder, the bucket
body 70 pivots about the pivot shaft 2.
[0082] The bucket 80 is movable to any position within a given
turning range by the operation of the backhoe body and can also
change its direction. The bucket body 70 of the bucket 80 is used
to scoop up raw material (material to be crushed), e.g. lumps of
asphalt or concrete, and to load them into the inside of the bucket
body 70 to crush and to transport pieces of crushed material.
[0083] The crusher bucket has in its bottom a discharge opening
for discharging pieces of raw material crushed to a predetermined
size, and further has a mesh grate 73 attached to the discharge
opening to adjust the particle size. The bucket has the function
of crushing raw material loaded therein by impacting it with hammers
74. The top of the bucket body 70 of the bucket 80 is provided with
an opening 82 for loading scrap or other raw material to be crushed.
A weir 72 serving as a material feed rate adjusting member is provided
on a scooping surface portion 71 defined by the bottom wall of the
bucket body 70. The weir 72 is preferably secured to the scooping
surface portion 71 by welding, deposition, bonding, or using securing
members such as bolts.
[0084] The weir 72 controls the feed of scooped raw material so
that the raw material will not be fed into the crushing chamber
70a at one stroke. That is, the amount of raw material passing over
the weir 72 and fed into the crushing chamber 70a is adjusted by
an operator adjusting the angle of pivot of the bucket body 70.
It should be noted that the outer wall surface of the weir 72 is
preferably covered with a rigid material.
[0085] A rotor shaft 9 is rotatably provided on the bucket body
70 and driven by a rotor driving device 10 disposed outside the
bucket body 70.
[0086] The rotor shaft 9 has a plurality of disks disposed thereon
at predetermined regular spacings (see FIG. 2). The rotor shaft
9 and the disks in combination constitute a rotor. Headed hammer
pivot shafts are provided to extend between each pair of adjacent
disks at respective positions on the outer peripheral portion of
each disk spaced from each other by a predetermined angle. The hammer
pivot shafts have hammers 74 pivotably provided thereon. The arrangement
of the hammer pivot shaft-and-hammer connecting mechanism is the
same as that described above with regard to the first or second
hammer removably securing mechanism. That is, each hammer 74 is
secured by a hammer retainer 35 or a combination of a first hammer
retainer member 55 and a second hammer retainer member 65.
[0087] The basic configuration of the hammers 74 is the same as
that of the above-described hammers 11 and 45. Therefore, a detailed
description thereof is omitted. The hammers 74 are preferably formed
by using a rigid and wear-resistant metallic material.
[0088] Thus, the rotor shaft 9 has a plurality of hammers 74 pivotably
secured thereto. When the rotor shaft 9 rotates, the hammers 74
repetitively strike (beat) and crush the raw material. The hammers
74 are mounted in such a manner as to be replaceable when becoming
worn or damaged. The hammers 74 are formed from a rigid and wear-resistant
metallic material. Thus, the hammers 74 are individually replaceable
with new ones when their striking surfaces have become worn or damaged.
[0089] When the crushing lid 76 is closed, the inside of the bucket
body 80 defines a crushing chamber 70a that is used to crush raw
material loaded thereinto (see FIG. 17). The inner wall of the crushing
chamber 70a is covered with a rigid material. The crushing lid 76
is provided on the top of the bucket body 70 in such a manner as
to be pivotable about a shaft 85 so as to be selectively opened
or closed. A lid opening-closing cylinder 83 is pivotably provided
through a shaft 86 on the bucket body 70 to allow the crushing lid
76 to be selectively opened or closed. A piston rod 83b of the lid
opening-closing cylinder 83 is connected to the proximal end portion
76b of the crushing lid 76 through a shaft 84.
[0090] During crushing of raw material in the crushing chamber
70a, the distal end portion 76a of the crushing lid 76 abuts against
the scooping surface portion 71 to prevent scattering of pieces
of crushed material from the opening 82 to the outside of the bucket
body 70. Accordingly, when the lid opening-closing cylinder 83 is
driven, the crushing lid 76 pivots about the shaft 85 provided on
the bucket body 70. Thus, the crushing lid 76 is opened or closed
in response to the operation of the cylinder 83. In FIG. 17 the
crushing lid 76 in its closed position is shown by the solid lines.
The crushing lid 76 in its open position is shown by the chain double-dashed
lines.
[0091] In response to the advancing or retracting movement of the
piston rod 83b, the crushing lid 76 pivots about the shaft 85 to
close or open the opening 82 of the bucket 80. The crushing lid
76 has a repulsion plate liner 77 for crushing secured to the inner
wall thereof. The repulsion plate liner 77 is formed in an approximately
V-shape in section such that the center thereof projects radially
inward of the crushing lid 76. The crushing lid 76 in the second
embodiment has a plurality of repulsion plate liners 77 secured
to the inner wall thereof. The repulsion plate liners 77 are formed
from a rigid material and individually replaceable with new ones
when they have become worn or damaged.
Raw Material Crushing Method by the Second Embodiment
[0092] The raw material crushing method carried out by the crusher
bucket 80 according to the second embodiment will be described below.
Raw material is scooped up by the forward end portion of the bucket
body 70 in a state where the crushing lid 76 is open, and loaded
onto the scooping surface portion 71 which is the front bottom
wall portion of the bucket body 70. At this time, the scooped raw
material is dammed up by the weir 72 so that it is not fed into
the crushing chamber 70a. After the crushing lid 76 has been closed,
the bucket body 70 is tilted so that the raw material is fed into
the crushing chamber 70a little by little by passing over the weir
72. At this time, the rotor shaft 9 is rotating in the direction
of the arrow Q. Therefore, the hammers 74 strike the raw material.
The raw material crushed by repetitive strikes of the hammers 74
collides against the repulsion plate liners 77 of the crushing lid
76 as well. Thus, the raw material is crushed little by little by
repetitive strikes of the hammers 11 collision against the repulsion
plate liners 77 collision between pieces of raw material, etc.
Pieces of crushed material are discharged through the grate 73 on
the bottom of the bucket body 70.
[0093] When all the scooped raw material has been crushed, the
crushing lid 76 is opened again. Then, raw material is scooped up
by the bucket body 70 and the above-described operation is repeated.
Thus, raw material is crushed in the bucket body 70 little by little
while the crushing rate and the shape and size of crushed particles
are adjusted by adjusting the tilt of the bucket body 70. Accordingly,
the rotating operation of the rotor shaft 9 is stabilized. In addition,
there is no possibility that raw material or pieces of crushed material
will be undesirably caught between the bucket body 70 and the hammers
74 etc., causing the rotor to be unable to rotate. It is also possible
to avoid an overload that might otherwise occur during crushing.
At the same time, the crusher according to the second embodiment
crushes raw material while preventing scattering of pieces of crushed
material. Therefore, it is possible to perform a crushing operation
that is favorable from the safety and environment point of view.
[0094] The raw material is crushed not only by impact but also
by repetitively rubbing against other raw material intermingling
therewith in the crushing chamber 7a as the rotor shaft 9 rotates.
Thus, the crusher according to this embodiment repeats the crushing
operation many times while impacting the raw material and therefore
can perform efficient crushing. In addition, raw material passing
over the weir 72 contacts the hammers 74 at an angle close to an
optimal one according to the theory of the material feeding angle
of the impact crusher inlet opening. Accordingly, efficient crushing
can be performed.
[0095] Further, because the crushing operation is carried out by
two rotor driving devices 10 the motor of each rotor driving device
10 need not be large in size. Accordingly, a well-balanced rotation
can be obtained for crushing. Pieces of raw material crushed to
a particle size less than a predetermined one are discharged to
the outside of the bucket body 70 from the grate 73 provided over
the discharge opening of the bucket body 70.
[0096] If raw material remains uncrushed in the bucket body 70
for some reason, the bucket body 70 is turned upside down, and the
raw material or coarse pieces of crushed material are discharged
from the opening 82.
[0097] It should be noted that the bucket 80 may be used in a 180-degree
inverted position. In such a case, the repulsion plate liners 77
play the role of the weir 72.
[0098] Although the present invention has been described by way
of embodiments, it should be noted that the present invention is
not necessarily limited to the foregoing embodiments but can be
modified in a variety of ways without departing from the object
and gist of the present invention. For example, the configuration
of the weir is not limited to the triangular configuration as seen
in a side view. The weir may have other configuration, for example,
a trapezoidal, quadrangular, semicircular, semielliptical or plate-shaped
configuration, or a combination of these configurations. The weir
may have any structure, provided that when the bucket scoops up
raw material, the weir dams up the raw material so that it is not
fed into the crushing chamber at one stroke, and the weir allows
the raw material to be fed into the crushing chamber over the weir
in a predetermined amount at a time when the bucket pivots through
a predetermined angle from the angle position where the raw material
was scooped up into the bucket. |