Note: Descriptions are shown in the official language in which they were submitted.
3L~8~39~
The present invention relates to vertical shaft impact
crushers, and more particu]arly to a vertical shaft impact
crusher capable of autogenous, semi-autogenous, or impact
crushing.
Impact crushers operate on the principal of accelerating
the rock to a high speed and causing it to impact agains-t a
target which will cause the rock to fracture. There are essen-
tially two -types of impact crushers: autogenoua impact crushers
and anvil impact crushers. The autogenous variety uses a bed of
the same material tha-t is being broken or crushed as the target
area so that the rock which is accelerated impacts against other
rock of the same type. Anvil type impact crushers utilize a
hard block of material such as manganese steel as the target
area.
The autogenous and anvil types of impact crushers are used
for different purposes. Autogenous crushing is used primarily
for reshaping rock whlch is already approximately the right
size. It is most frequently used on wash gravel or natural rock
which is smooth and needs to be reshaped with flat faces so that
: 20 it aan be used as aggregate in CODCrete and the like.
Autogenous cxushlng also producas a large number o~ fines, so
that most of the product of autogenous breaking or crushing is
at the two extreme ends;of the product~size spectrum. However,
this crushing medium requires higher rotor tip velocities to
achieve desirable reduction ratios. Higher ro-tor speeds in-
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crease horsepower requirements and substantially increase rotor
wear.
Anvil breaking, on the other hand, pro~uces a shattering
action on the rock so that the majority of the product is near
the centra] region of the product size distribution spectrum.
Anvil breaking is used primarily to reduce the size of the input
rock rather than to reshape rock which is already approximately
the correct size. The anvil crushing ring thus generates higher
reduction ratios at slower tip velocities, but does not generate
a product shape of comparable quality to the autogenous ap-
paratus, commonly known as the "rock box". The anvil ring
reduces horsepower requirements and minimizes rotor wear by al-
lowing for lower rotor speeds.
Impact rock crushers are often mounted on trailsrs for
transportation from site to sitel SG that rock may be crushed at
the location where it is needed. ~owever, in the past, it has
been necessary to use an autogsnous arusher for autogenous
crushing and to use an anvil crusher for anvil crushing. One
solution to this problem is disclosed in commonly-assigned U.S.
Patent 4,560,113, where a vertical shaft impact crusher is pro-
vided with a pair of interchangeable breaker rings; one having
anvils for impact crushing, and the other with a rock box for
autogenous crushing. Thus, in this case the operator has a
choice of performing either shaping or size rsduation, but not a
combination of both.
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Thus, there has been a need for a vertical shaft impact
crusher which is capable of adjusting or fine tuning the crushing
process to more accurately control the size and shape of the
crushed product.
We have ~ound that the above disadvantages may be
overcome by providing a vertical shaft impact crusher with a
crusher ring which includes segmented interchangeable and
alternating crushing portions, each portion designed for one of
the three types of crushing mentioned above.
The present invention provides a vertical shaft impact
crusher for crushing rock or minerals, including a housing having
an outside surface, an inside surface and a cover plate with an
underside, a rotor mounted wi-thin said housing for rotation about
a central vertical axis and designed to receive axially-fed rock
and propel it outwardly towards the inner surface of said housing,
means for rotating said rotor about said a~is, an annular crusher
ring releasably and adjustably mounted to the inner surface of
said housing, said crusher ring comprising a plurality of impact
breaker anvil brackets secured to and positioned around said
crusher ring; a plurality of impact breaker anvils removably
positioned in a select number of said brackets to receive and
fragment rock thrown by said rotor; a plurality of autogenous
plate retaining brackets secured to and regula~ly spaced about~....
said crusher ring beneath said anvil brackets; and a plurality of
subs~antially planar autogenous plates, each having an inner
peripheral edge and being releasably secured to said crusher ring
by said plate retaining brackets in a selected radially inwardly
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projecting orientation to form at least one rock-retaining ledge
segment beneath said anvil brackets which~ when filled with rock,
performs autogenous crushing; wherein the selected sequence of
autogenous plates and breaker anvils around said ring creates
autogenous crushing portions, impact crushing portions and/or
semi-autogenous crushing portions on said crusher ring to allow
the size and shape of said rock passing through said crusher to be
precisely regulated.
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~8~39
The preferred embodiment of this invention will now be de-
scribed by way of example, with reference to the drawings ac-
companying this specification in which:
Fig. 1 is a sectional elevation of the vertical shaft im-
pact crusher made in accordance with this invention;
Fig. 2 is a partial sectional perspective of the vertical
shaft impact crusher shown in Fig. 1 with the cover and rotor
removed and a fragment of the crusher ring exploded out of the
machine;
Fig. 3 is a plan view of the rotor and crusher ring of the
present invention wherein a combination of autogenous, impact
and semi-autogenous crushing may be performed;
Fig. 3A is an enlarged plan view of a portion of the
crusher ring of the present invention depicted in Fig. 3 with
the anvil brackets removed;
Fig. 4 is a section of one portion of the present crusher
ring in the semi-autogenous mode;
Fig. 5 is a sec-tion of a segment of the present crusher
ring in the autogenous modei and
Fig. 6 is a section of a ~egment of the present crusher
ring in the semi-autogenous mode wherein a supplemental annular
rock retention ring is provided attached to the inner surface of
the top lid.
Referring now to the drawings, wherein like reference
characters designate identical or corresponding parts, and more
particularly to Figs. 1 and 2, a vertical shaft impact crusher
~ 2~3239;~ !
accordi.ng to the present invention includes a frame 10 on which
is mounted a drive motor 12, a crusher housing 14 bolted to the
frame concentrically around a pair of segmental openings 15
therethrough and a crane 16. A bearing cartridge 20 is also
moun-ted directl~ to the frame 10 coaxially within the crusher
housing 14. The bearing cartridge 20 supports for rotation
about a vertical axis a shaft 22 which has mounted on its top
end a rotor 24 and mounted on its lower end, a sheave 26 which
is connected by way of a drive belt 28 to a corresponding sheave
30 mounted on the lower end of the motor shaft 32.
A cover 34 is mounted on top of the crusher housing 14 and
includes a feed tunnel 36 mounted on a collar 38 which is welded
to a cover plate 40 concentrically with a central hole 42 and
the cover plate ~0. A series of radially extending tapered
braces 44 are welded to the collar ~8 and to the cover plate 40
to strengthen the cov;r and provide, by virtue of holes 45 in
the braces 44, means for attaching a hoist cable from the crane
16 when it is desired to lift the cover off of the crusher hous-
ing 14.
The feed tunnel 36 has a floor plate 48 having a central
opening 50. A feed tube 52 lS welded to the underside of the
floor plate 48 and depends therefrom to a level approximately
equal to that of the cover plate 40. A replacement feed tube
extension 54 is telescopically disposed around the feed tube 52
and is provided with an extension adjustment mechanism for ad-
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justing the length of its extension through -the hole 42 in the
cover plate 40.
A guard shell 63 made of a series of shell se~ments 64 is
bolted to the underside of the cover plate 40 concentrically
around the central hole 42. The shell segments are arcuate in
form and include an inwardly extending upper flange by which the
segments 64 are bolted to -the cover plate. The liner segments
64 protect the top of the rotor 24 from damage by broken rock
bouncing off of a crusher ring 70 mounted in the crusher housing
14 as to be horizontally aligned with the rotor 24.
The crusher ring 70 shown in Fig. 1 and shown in greater
detail in Figs. 2-6 includes an annular hoop 72 of heavy steel
construction having an annular seal 73 fastened to its top sur-
face for sealing space between the hoop 72 and the crusher hous-
ing 14. Three or four depending vertical legs 74 are welded to
the underside of the hoop 72 at equally spaced annular positions
around the hoop~ The exact number of legs will be determined by
the load càpaclty of the ring 70. The legs 74 are supported by
a like number of stepped mounting blocks 76 wslded -to the inside
o the arusher housing 14, as shown most clearly in Fig. 2. The
support blocks 76 have a plurality of steps formed thereon at
different angular positions and elevations to provide a
plurality of elevation settings for the crusher ring. This
enables the elevation of the crusher ring to be adJusted within
crusher houslng 14 so that the vertical position of the crusher
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~28~39~
ring relative to the rotor can be optimized for optimal crushing
efficiency and use of material, as explained more fully below.
The crusher ring 70 has welded thereon a series of brackets
78, each having twc legs 77 fastened to and extending inwardly
from the hoop 72 on a secant to the circle defined by the hoop.
A cross arm 79 is welded to and extends between the outside end
of each pair of legs 77 and has a vertical slot 81 completely
through the arm 79. The cross arm 79 is actually made of two
separate pieces, one each welded to the end of each leg 77.
Three lifting lugs 75 are welded to three legs 77 at equally
spaced angular positions around the crusher ring for attachmen-t
of a cable to hoist the crusher ring in and ou-t of the housing
14.
Each bracket 78 may support an anvil 80. Each anvil 80 in-
cludes an octagonal head 82 having a flat octagonal face 83, a
square foot 84, and square neck 86 connecting the head 82 and
the foot 84. The head, foot and neck of the anvil 80 are sym-
m~trical about a horizontal axis 88 forming an angle ~ with a
-tangent 87 o-f the rotor through the anvil of about 5-15, with
10 being preferred as shown in Fig. 3. This angle represents
the radial component of velocity exerted by the rotor on the
rock as it is propelled from the rotor. The radial component of
velocity is a function of the rotor pocket face angle, as dis-
cussed below.
Each anvil 80 is supported on a bracket 78 by lowering the
anvil neck 86 into the slot 81 in the aross arm 79 un-til the
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anvil foot 84 contacts a support plate 89 welded to the bo-ttom
of the bracket legs 77 and cross arm 79. The support plates 89
support the vertical weight of the anvil 80 and also rigidify
the brackets 78.
The brackets 78 are welded from simple flame cut pieces for
great economy and precision of manufacture, and also great
strength. The pieces all overlap each other slightly to provide
a convenient and economical outside rabbets in which the pieces
can be quickly and securely welded. The structure is so open
and accessible that it is particularly suitable for automatic
welding operations.
The octagonal faces 83 of the anvil head 82 represent an
efficient utilization of anvil material, since the corners of a
square or rectangular anvil are not impactsd by rock in a
centrifugal impact crusher of the present design. The octagonal
face is symmetxical about the axis 88 of the anvil so that the
anvil may be rotated by multiples of 90 without changing the
pattern of anvil faces presented to the rotor 24. It is thus
possible to mainta1n a substantially uniform and consistent
anvil array throughout the useful life of the anvil. The sup-
port blocks 76, spaced at equal angular positions around~the
crusher housing 14, snable the~crusher r1ng 70 to be rotated to
as many positions as there are sùpport blocks 76~ four being
disclosed herein. In practice, the rocks tend to be -thrown
predominantly in one angular region where they tend to fall into
the rotor prsdominantly toward one side because of the conveyor
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eeder. Consequently, the anvils 80 in that one angular region
tend to wear faster than in other regions. By pariodically
rotating the breaker ring incrementally, it is thus possible to
distribute the anvil wear more evenly.
The rotor, as seen in Figs. 1 and 3, includes a circular
base plate 90 having an axial hub 92 ormed integrally on the
vsrtical center line 94 o the rotor. A top plate 96 is d~s-
posed vertically above and parallel to the base plate 90 and
coaxial therewith. The top plate 96 is held in spaced rela-
tionship to the base plate 90 by a series of vertically orientedpartitions or plates which form four autogenous pockets 98
spaced equally around the rotor. Each pocket 98 is formed of an
arcuate circumferential or peripheral plate 100 and a radial
plate 102 welded to the trailing end of the circumferential
plate 100 in the sense of the direc-tion of rotation thereof. A
pocket floor plate 104 is welded at an angle ~ o about 76 be-
tween the radial plate 102 and the ~arcuate plate 100~ The angle
~ is selected to lie approximately parallel to the top face 106
of the dirt and rock bed which collects and is held in pocket 98
while the machine is in operation, although the angle of face
106 may be adjustable by the -technique disclosed below. The
pocket floor plate 104 reduces the mass of the rock in the pock-
et to minimize the severity o the imbalance if one rock bed be-
comes dislodged.
The leading edge of each arouate plate 100, on the end
remo-te from the end to which the radial plate 102 is connected,
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has attached thereto a wear resistant bar 110~ The wear
resistant bar 110 is attached to the leading edge of the arcuate
plate 100 by two bolts 112 which pass through a back-up bar 114
on the outside of the arcuate plate 100 to protect the bolts 112
from erosion by broken rock ricoche-ting off the anvils 80. The
leading inside edge of the wear resistant bar 110 includes a
slot in which is fixed, as by silver soldering, a piece of hard,
wear resistant material 116 such as silicon carbide.
The radial inside edge of the radial plate 10~ is protected
from erosion by a wear bar 118. The wear bar 118 is an L-shaped
member which is held in place on the radial plate 102 by tack
welding and is removed by burning through the tack weld with a
torch. The wear bar 118 is made of a high chrome steel and does
not require tha silicon carbide insert as used in the wear bar
110 because the wear bar 118 is much closer to the axis of the
rotor than the wear bar 110, so it is not sub~ected to the same
degree of erosive action that the wear bar 110 experiences as
rocks are accelerated off its feeding edge.
The angle selected for the ace 105 of the rock bed in the
pocket 98 is controlled by the length of the radial plate 102
and the eec-tive length of tha peripheral arcuate plate 100.
The effective length of both plates can be varied by the use of
different wear bars 110 and 118 having greater length so they
effectively extend past either the radial plate 102 (for a smal-
ler angle ~ of the face of the rock bed) or the arcuate plate
100 (for a greater angle ~ of the rock bed face).
~L2 82 ;3i 92
To increase the shattering effect of -the rotor itself on
the rock, it may be desirable to replace the autogenous rotor
pocket structure with conventional cast iron impeller shoes.
The rotor 24 of this invention will accommodate the installation
of conventional shoes mounted directly to the walls 100, 102 and
104, or could be mounted directly to the rotor base plate 90 in
place of the autogenous pocket walls.
A pair of wear plates 120 and 122 is fixed to the rotor
base plate 90 and the rotor top plate 96, respectively, in each
of the four quadrants of the rotorO The bottom wear plate 120
is fixed to the top surface of the rotor base plate 90 by a pair
of bolts 124 which pass through the wear plate 120 and the rotor
base plate 90 and are locked into position by suitable locking
nuts.
A protective skirt or lower outer guard ring 142 is tack
welded around the outside periphery of the rotor base plate 90,
projecting vertically slightly above the top surface thereo~ and
vertically below the top surfaces thereof a distance approxi-
mately equal to the thickness of the rotor base plate 90. The
skirt 142 protects the edge of the rotor base plate 90 from ero-
sion and also provides a shoulder by which the position of the ;
bottom wear plate 120 can be located for ease of insertion of
the mounting bolts when the wear plate 120 is replaced.
A top guard ring or rim 144 is welded to the rotor top
plate 96 in the same manner used to weld the protective skirt
142 to the rotor base plate 90. The top of the top rim 144
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proj~cts above the top surface of the top plate 86 and forms a
shoulder 145 therewith.
The skirt 142 and the top rim 144 provide a prestressed
support ring to radially support the wear plates 120 and 122.
Under high centrifugal force, the skirt and rim, if not
prestressed, could expand slightly and lessen the radial support
provided to the wear plates.
The rotor hub 92 is held to the top of the shaft 22 by a
conventional key arrangement.
The shaft 22 is suppor-ted by a cylindrical bearing
cartridge 20 shown bes-t in Fig. 2~ A heavy cylindrical
cartridge housing 154 is attached to a bridge 155 ln the base of
frame 10 between the two segmental openings 15 by bolting a
lower flange 156, integral with the housing 154 and into which
is drilled a ~lurality of holes to receive bolts 160 by which
the bearing cartridge housing 154 is fastened to the frame
bridge 155.
A cylindrical dust shell 194 surrounds the bearing
cartridge 20 and is supported thereon by a radially inwardly ex-
tending flange 196 which is bolted to a radially outwardly ex-
tending flange 198 adjacent the top of the cartridge housing
154. A rubber bumper 200 1s fitted on the lower end of the dust
shell 194 and is slightly compressed between the dust shell and
the frame 10 to exclude dust from the bearing cartridge and to
dampen vibration and minimize noise. A urethane shield 202 is
secured to the outside surface of the dust shell 194 to prevent
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12~323~32
abrasive damage to the dust shell and also to dampen vibration
and minimize noise. The urethane shield 202 may be bolted to
the dust shell or may be bonded directl~ to the shell.
Referring now to Figs. 1 and 2, the crusher housing 14 is a
cylindrical tank having a rubber bumper 222 placed on the top
lip of the tank to act as a dust seal and also to dampen vibra-
tion and to attenuate noise. An annular bracket 224 is welded
around the outside surface of the tank slightly below the top
lip and provides a support to which the bottom edge of a
plurality of upright locking tongues 226 are weld~d. Each lock-
ing tongue has a rectangular hole 228 punched in its upper end
for receiving a lock wedge 230. The cover plate 40 has a series
of short radial slots 232 at its outside edge at angular posi~
tions corresponding to the angular positions of the locking ~`
tongues 226 around the housing 1~, so that when the cover is
placed on the top of the housing 14 with the locking tongues
lined up with the slots 232, the tongues 226 will extend through
the slots 232 and the lock wedges 230 may be driven into the
holes 228 to lock the cover in place.
A series of spacer blocks 234 is welded on a horizontal
line around the inside of the tank just beneath the stepped sup-
port block 76. The spacer blocks 234 are each drilled and
tapped to accept a bolt 236 which fastens a rubber curtain 238
at its top edge to the spacer blocks. The rubber curtain 238
hangs down to the floor around ths full inside circumference of
the crusher housing 14. It prevents abrasion of the tank wall
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and is extremely effective in dampening vibration and noise dur-
ing operation.
The crusher ring 70 can be removed by attaching a cable
hook -to each of the three lifting lugs 75 attached to the three
bracket legs 77 at equally spaced positions around the annular
hoop 72 of the crusher ring 70 and lifting the crusher ring out
of the crusher housing 14.
The preceding discussion has described a vertical shaft im-
pact crusher capable of anvil crushing exclusively. Purely
autogenous crushers are also well known in the prior art. How-
ever, many applications call for a crushed product which is best
obta~ined through a combination of anvil and autogenous crushing.
Until the present invention, such a combination was unavailable
on a single crushing ring 70.
In the present invention, and referring to Figs. 2, 3, 3A
and 5, autogenous crushing is obtained through the use of at
least one removable flat plate 280 which extends on a substan-
tially horizontal plane from the crusher ring 70 towards the
rotor 24. Each plate 280 may be provided around its inner
periphery with a vertiaally projecting flange 282 to facilitate
the retention of a sufficient quantity of rock to form an
autogenous bed 284. The plates 280 are releasably secured to
the crusher ring 70 by being placed upon a pair of supporting
gusset members 286 and an annular bracket 283. The gussets 286
are constructed and arranged to support two adjacent plates 280.
Bracket 283 is provided with radially pro;ecting portions 285
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and is secured to the lower edge of the crusher ring 70 to sup-
port plate 280. Each gusset 286 is provided with a pair of
vertically projecting locating lugs 287 located at the protrud-
ing end of gusset 286. Lugs 287 are positioned to ~ngage
notches 288 on each lateral edge of plates 280 to locate and
position the plates upon crusher ring 70. Plate 280 is thus
secured without the use of supplemental fasteners or tools.
Once the crusher is in operation, the pla-tes 280 will be secured
upon ring 70 by the accumulation of crushed rock which forms the
autogenous bed 284.
In some oases, semi-autogenous crushing may also be
desired. As is shown in Fig. 4, the autogenous retention plate
280 is placed in a por-tion of the crusher ring 70 and is ac-
companied by an anvil which has been placed in ths bracket 78.
Specifically referring to Fig. 3, it can be seen that the
radially projecting portions 285 of annular bracket 283 roughly
divide the crusher ring 70 into a plurality of seg~ents 289, tha
number of segments approximating the number of radially pro;ect-
ing portions 285. Each segment 289 may be provided with an
anvil 80, a plate 280, both plate and anvil, or neither feature.
In addition, groups of adjacent segments may be similarly out-
fitted to achieve the same crushing characteristics. Further-
more, the crusher ring 70 may be outfitted so tha-t the crushing
characteristics of one segment 289 overlap the ad;acent segment.
For example, in a segment fitted with two anvil brackets 78, an
anvil may be placed in only one bracket, and a plate 280 may be
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lZ8~39~
included to create a segment with semi-autogenous and autogenous
characteristics.
Raferring now to Fig. 6, in order to further cover the
anvil with a layer of autogenous rock on its upper surface, the
interior of cover plate 40 is provided with an annular, verti-
cally depending ring 290 which, when cover 40 is in place,
creates an additional retention area for crushed rock. This an-
nular ring 290 may be provided in segmental form to further ad-
~ust the shaping and sizing of the particular products of the
crusher. The use of a ring segment 290 is not restricted to
those portions conta~ning anvils, but may also be placed over
crusher ring portions designed for autogenous and/or semi-
autogenous crushing.
The crane 16 includes a support pillar 254 to which a pair
of brackets 256 are attached for supportiny a crane control box
by which the crane 16 is controlled. A bearing (not shown)
around the upper portion of the support pillar 254 rotatably
supports the upper end of the crane 16 which includes a vertical
extension 260 and a cantileverad horizontal arm 262. A support
bracket 264 is welded to the lower end of the vertical extension
260 and supports an electric motor 266 ooupled to a gear pump~
268.
A hydraulia rotation motor (not shown) is coupled between
the upper portion of the crane 16 and the support pillar to
allow the upper portion of the crane to be rotated about the
support pillar. A motorized hydraulic winch 272 allows a hook
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274 to be raised or lowered by taking up or playing out cable
from a winch drum tnot shown).
In operation, rock to be crushed is continuously fed into
the feed tunnel 36 and falls through the feed tube 52 and the
feed tube extension 54 and into the center of the rotor 2~. The
rotor rotates at variable speeds on the order of about 900-1800
RPM. The rock is thrown radially outward where it is caught and
accelerated by the rotor pockets 98. The rotor pockets soon be-
come covered with a blanket of rock which protects them from
erosion by the rock as it is thrown outward. The only surfaces
which encounter erosion within the pocket are the wear plates
120 and 122 and the inner and outer wear bars 118 and 11~.
These wear pieces are all easily and ~uickly replaceable when
they wear down.
The rock is thrown by the pockets 98 outwardly against ei-
ther the anvil breaker 80, the autogenous bed 284 or the semi-
autogenous portion 292. The trajectory o the roak is about 5-
15 out from the tangent to the rotor. The deviation from
tangential trajectory is caused by the angle of the rock face
within the pocket 98 and the coefficient of friction of the
rock~on-rock as the rocks are thrown radially outward. The
brackets 78 are set in the crusher ring 70 at an angle such that
the faces of the anvils 80 lie perpendicular to the flight
trajec-tory of the rock which is about 10 out of tangent to the
rotor. In this way, the rocks will strike the anvil faces ex-
actly perpendicular so that the full momentum of the rock is
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converted to an internal shattering force and little of the en-
ergy is wasted on ricochet force. The broken rock then falls
vertically downward between the rubber curtain 238 and the dust
shell 194 and through the openings 15 on the two sides of the
cartridge support bridge 155. The rock is then carried away by
suitable conveyor means (not shown).
Faced with very specific product needs, the crusher opera-
tor will determine the desired combination of anvil, autogenous
bad, or semi-autogenous crushing characteristics to create the
most desirable product. The crusher ring segments 290 are then
assembled so as to have the desired combination of character-
istics by removing or combining anvils 80 with plates 280,
andtor lid segments 290, as is shown in Fig. 3. If desired, a
totally autogenous, totally semi-autogenous or totally impact
breaker type crusher ring may also be provided.
Obviously, numerous modifiaations and variations of the
above-described preferred embodiment will occur to those skilled
in the art in light of this disclosure. Accordingly~ it is ex-
pressly to be understood that these modifications and varia-
tions, and the equivalents thereof, may be practiced whileremaining within the spirit and scope of this invention as
defined in the following claims.
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