Abstrict A cone crusher having a main frame, a crusher head interconnected
with the main frame, a crusher bowl positioned adjacent to the first
crusher member, and a double-acting hydraulic lift interconnected
with both the main frame and the second crusher member. A force
transfer member extends downward relative to the crusher bowl. The
hydraulic lift includes an upper end interconnected with the main
frame and a lower end interconnected with the force transfer member,
thereby providing a downward clamp force on the force transfer member
to compliantly clamp the crusher bowl to the main frame in an operating
position. The hydraulic lift can provide an upward lift force on
the force transfer member to move the second crusher member from
the operating position to a clear position.
Claims What is claimed is:
1. A method of converting a mechanical spring cone crusher to a
hydraulic spring cone crusher, the mechanical spring cone crusher
including a main frame, an adjustment ring, a spring bolt, a mechanical
spring, and a lower spring segment, said method comprising the steps
of:
(a) removing the lower spring segment and the mechanical spring
from the cone crusher;
(b) securing the spring bolt to the adjustment ring;
(c) positioning a hydraulic spring assembly adjacent to the main
frame; and
(d) securing the lower spring segment to both the hydraulic spring
assembly and the spring bolt.
2. The method of claim 1 wherein step (b) comprises welding the
spring bolt to the adjustment ring.
3. The method of claim 1 wherein the hydraulic spring assembly
includes a cylinder member, and wherein step (c) comprises:
(e) providing a first support flange and a second support flange;
(f) interconnecting the first flange with the main frame;
(g) interconnecting the second flange with the main frame; and
(h) positioning the hydraulic spring assembly such that the cylinder
member is between the first and second flanges.
4. The method of claim 3 wherein the hydraulic spring assembly
is a double acting hydraulic lift operable between an operating
position and a clear position; and wherein step (g) comprises:
providing a bracket;
welding the bracket to the main frame; and
fastening the second flange to the bracket;
and wherein step (h) comprises:
providing a first resilient pad and a second resilient pad;
interconnecting the first resilient pad with a top surface of the
cylinder member;
interconnecting the second resilient pad with the second flange;
and
positioning the hydraulic spring assembly such that a portion of
the cylinder member compresses the first resilient pad when the
hydraulic spring assembly is in the operating position, and a portion
of the cylinder member compresses the second resilient pad when
the hydraulic spring assembly is in the clear position.
5. The method of claim 1 wherein the hydraulic spring assembly
includes: a piston member having formed therein a threaded bore;
a piston bolt; and a cylinder member in telescoping relationship
with the piston member and movable with respect to the piston member
between an operating position and a clear position; and wherein
step (d) comprises:
(i) forming an aperture in the lower spring segment, the aperture
extending through the lower spring segment;
(j) passing the piston bolt through the aperture;
(k) threading the piston bolt into the bore; and
(l) connecting the spring bolt to the lower spring segment.
6. The method of claim 5 wherein step (l) comprises:
providing an upper nut and a lower nut;
threading the upper nut onto the spring bolt;
positioning the lower spring segment on the spring bolt; and
threading the lower nut onto the spring bolt such that the lower
spring segment is captured between the upper nut and the lower nut.
7. The method of claim 6 wherein:
step (b) comprises welding the spring bolt to the adjustment ring;
and
step (c) comprises:
providing a first support flange, a second support flange, a first
resilient pad, a second resilient pad, and a bracket;
interconnecting the first flange to the main frame;
welding the bracket to the main frame;
fastening the second flange to the bracket with a screw;
connecting the first resilient pad to a top surface of the cylinder
member;
connecting the second resilient pad to the second flange; and
positioning the hydraulic spring assembly such that a portion of
the cylinder member compresses the first resilient pad when the
hydraulic spring assembly is in the operating position, and a portion
of the cylinder member compresses the second resilient pad when
the hydraulic spring assembly is in the clear position.
8. The method of claim 1 wherein said mechanical spring cone crusher
includes a plurality of spring bolts, a plurality of mechanical
springs, and a plurality of lower spring segments, and wherein step
(a) includes removing said plurality of lower spring segments and
said plurality of mechanical springs from the cone crusher, step
(b) includes securing each of said plurality of spring bolts to
the adjustment ring, and step (d) includes securing said plurality
of lower spring segments to both the hydraulic spring assembly and
said plurality of spring bolts.
9. A method of converting a mechanical spring cone crusher to a
hydraulic spring cone crusher, the mechanical spring cone crusher
including a main frame, an adjustment ring, a spring bolt, a mechanical
spring, and a lower spring segment, said method comprising the steps
of:
(a) providing a hydraulic spring assembly having a cylinder member;
(b) removing the lower spring segment and the mechanical spring
from the cone crusher;
(c) securing the spring bolt to the adjustment ring;
(d) providing a first support flange and a second support flange;
(e) interconnecting the first flange with the main frame;
(f) interconnecting the second flange with the main frame;
(g) positioning the hydraulic spring assembly such that the cylinder
member is between the first and second flanges; and
(h) securing the lower spring segment to both the hydraulic spring
assembly and the spring bolt.
10. The method of claim 9 wherein the hydraulic spring assembly
is a double acting hydraulic lift operable between an operating
position and a clear position; and wherein step (f) comprises:
providing a bracket;
welding the bracket to the main frame; and
fastening the second flange to the bracket;
and wherein step (g) comprises:
providing a first resilient pad and a second resilient pad;
affixing the first resilient pad to a top surface of the cylinder
member;
affixing the second resilient pad to the second flange;
and
positioning the hydraulic spring assembly such that a portion of
the cylinder member compresses the first resilient pad when the
hydraulic spring assembly is in the operating position, and a portion
of the cylinder member compresses the second resilient pad when
the hydraulic spring assembly is in the clear position.
11. The method of claim 9 wherein the hydraulic spring assembly
includes: a piston bolt; a piston member in telescoping relationship
with the cylinder member and movable with respect to the cylinder
member between an operating position and a clear position, the piston
member having formed therein a threaded bore; and wherein step (h)
comprises:
(i) forming an aperture in the lower spring segment, the aperture
extending through the lower spring segment;
(j) passing the piston bolt through the aperture;
(k) threading the piston bolt into the bore; and
(l) connecting the spring bolt to the lower spring segment.
12. The method of claim 11 wherein step (l) comprises:
providing an upper nut and a lower nut;
threading the upper nut onto the spring bolt;
positioning the lower spring segment on the spring bolt; and
threading the lower nut onto the spring bolt such that the lower
spring segment is captured between the upper nut and the lower nut.
13. A method of converting a cone crusher having a mechanical spring
assembly to a cone crusher having a hydraulic spring, the cone crusher
having a mechanical spring assembly including a main frame, an adjustment
ring, a spring bolt, a lower nut, a mechanical spring, and a lower
spring segment, said method comprising the steps of:
(a) providing a hydraulic spring assembly including a cylinder
member, a piston member in telescoping relationship with the cylinder
member, and a piston bolt having a piston bolt head;
(b) removing the mechanical spring assembly from the cone crusher;
(c) welding the spring bolt to the adjustment ring;
(d) drilling a hole in the lower spring segment;
(e) passing the piston bolt through the hole;
(f) threading the piston bolt into the bore such that the lower
spring segment is captured between the piston bolt head and the
piston;
(g) threading the lower nut onto the spring bolt such that the
cylinder member and the piston member are captured between the lower
spring segment and a portion of the main frame.
14. The method of claim 13 further comprising the steps of:
providing a support flange, a first resilient pad, and a second
resilient pad
affixing the first resilient pad to a top surface of the cylinder
member;
affixing the second resilient pad to the support flange;
connecting the flange to the main frame;
positioning cylinder member between the second resilient pad and
a portion of the main frame; and
providing an upper nut;
and wherein step (g) further comprises:
threading the upper nut onto the spring bolt;
positioning the lower spring segment on the spring bolt; and
threading the lower nut onto the spring bolt such that the lower
spring segment is captured between the lower nut and the upper nut.
15. A method of converting a cone crusher having a mechanical spring
assembly to a cone crusher having a hydraulic spring assembly, the
cone crusher having a mechanical spring assembly including a main
frame, an adjustment ring, a spring bolt, a lower nut, a mechanical
spring, and a lower spring segment, said method comprising the steps
of:
(a) providing a hydraulic spring assembly including a cylinder
member, a piston member in telescoping relationship with the cylinder
member and defining a threaded bore, and a piston bolt;
(b) removing the lower spring segment and the mechanical spring
assembly from the cone crusher;
(c) welding the spring bolt to the adjustment ring;
(d) providing a support flange, a first resilient pad, and a second
resilient pad;
(e) affixing the first resilient pad to a top portion of the cylinder
member;
(f) affixing the second resilient pad to the support flange;
(g) connecting the support flange to the main frame;
(h) positioning the hydraulic spring assembly such that the cylinder
member is positioned between the first resilient pad and a portion
of the main frame;
(i) drilling a hole in the lower spring segment;
(j) passing the piston bolt through the hole;
(k) threading the piston bolt into the bore;
(l) providing an upper nut;
(m) threading the upper nut onto the spring bolt;
(n) positioning the lower spring segment on the spring bolt; and
(o) threading the lower nut onto the spring bolt such that the
lower spring segment is captured between the upper nut and the lower
nut.
16. The method of claim 15 wherein the cylinder member and the
piston member are movable with respect to each other between an
operating position and a clear position, and wherein step (h) further
comprises positioning the cylinder member such that the first resilient
pad is compressed between the cylinder member and a portion of the
main frame when the hydraulic spring assembly is in the operating
position, and the second resilient pad is compressed between the
cylinder member and the support flange when the hydraulic spring
assembly is in the clear position .
Description FIELD OF THE INVENTION
The present invention generally relates to the field of crushers
used to crush aggregate into smaller pieces. More specifically,
the present invention relates to cone crushers having clamp springs
for compliantly holding a crusher bowl liner down against a crusher
mantle during a crushing operation.
BACKGROUND OF THE INVENTION
Crushers are used to crush large aggregate particles (e.g., rocks)
into smaller particles. FIGS. 1 and 2 illustrate one particular
type of crusher, known as a cone crusher 12. In the illustrated
cone crusher 12 large particles are fed to a feed distributor 14
(FIG. 2) where the particles are distributed into a feed hopper
16. Referring specifically to FIG. 2 the large particles fall into
an annular space 18 between a bowl liner 20 and a mantle 22. The
bowl liner 20 is secured to a bowl 24 which is threaded to an adjustment
ring 26. The threaded interconnection allows the height of the bowl
24 to be adjusted relative to the adjustment ring 26 thereby accommodating
a range of particle sizes. Hydraulic lock posts 28 can be used to
selectively lock the adjustment ring 26 to the bowl 24.
The adjustment ring 26 is clamped to, but can move vertically relative
to, a main frame 30 as described below in more detail. Alignment
pins 31 maintain the adjustment ring 26 in alignment with the main
frame 30. The mantle 22 is secured to a head 32 which is, in turn,
secured to a main shaft 34. The main shaft 34 is eccentrically and
rotatably mounted in a eccentric 36 which is, in turn, rotatably
mounted in the main frame 30. The eccentric 36 is driven by a countershaft
38 through a pinion 40 that is secured to the countershaft 38 and
a gear 42 that is secured to the eccentric 36.
Because of the eccentric mounting of the main shaft 34 (and associated
head 32 and mantle 22) within the eccentric 36 the annular space
18 between the bowl liner 20 and the mantle 22 is not uniform. Rather,
the space 18 varies about the circumference of the mantle so that
the spacing includes a relatively large gap on one side of the mantle
and a relatively small gap on the other side of the mantle. When
the eccentric 36 is driven, the main shaft 34 (and associated head
32 and mantle 22) circumscribes an annular path (i.e., due to the
eccentric mounting), thereby causing the large and small gaps to
similarly travel in an annular path. This gyrating motion of the
head 32 and the mantle 22 around the main axis of the cone crusher
allows the feed material to enter the annular space 18. The material
is then impacted and compressed between the mantle 22 and the bowl
liner 20 in a series of steps as the material travels further down
the annular space 18. The annular space 18 progressively gets smaller,
thereby reducing the feed material down to the desired product size.
During crushing operations, it is not uncommon to encounter particles
that are difficult to crush, sometimes referred to as "tramp."
Small tramp will generally pass through the system without difficulty.
However, sometimes even small tramp will become lodged between the
mantle 22 and the bowl liner 20. In this situation, by virtue of
the vertical movability of the adjustment ring 26 the bowl liner
20 will raise slightly to allow the small tramp to pass through
the crusher. Such vertical movability of the adjustment ring 26
(and associated bowl 24 and bowl liner 20) is provided by a coil
spring assembly 44 that clamps the adjustment ring 26 to the main
frame 30.
In the illustrated crusher 12 the coil spring assembly 44 comprises
sixteen coil spring subassemblies 46 circumferentially spaced around
the main frame 30. Each coil spring subassembly 46 includes an upper
frame flange 48 secured to the main frame 30 a lower spring segment
50 and five coil springs 52 between the upper frame flange 48 and
the lower spring segment 50. Three spring bolts 54 extend through
the lower spring segment 50 the upper frame flange 48 and the
adjustment ring 26. Spring nuts 56 are secured to the lower end
of each spring bolt 54. In the illustrated arrangement, the coil
springs 52 bear against the underside of the upper frame flange
48 and push down on the lower spring segment 50 which in turn
pulls down on the spring bolt 54 and nut 56 and associated adjustment
ring 26.
The above-described arrangement affords upward movement of the
adjustment ring 26 (and associate bowl 24 and bowl liner 20) against
the force of the coil springs 52 in response to engagement of the
bowl 24 and mantle 22 with tramp material, thereby allowing small
tramp to pass through the system. It should be appreciated that,
due to compression of the coil springs 52 any vertical movement
of the adjustment ring 26 results in increased pressure being provided
by the bowl liner 20 against the particles. The initial clamping
force provided by the coil spring assembly 44 (i.e., before the
adjustment ring 26 raises from the main frame 30) is on the order
of about one million (1000000) pounds.
When large tramp particles become lodged in the annular space 18
the pressure created between the tramp, bowl liner 20 and mantle
22 can be so large that it causes the motor (not shown) driving
the countershaft 38 to stall. In this situation, the tramp must
be cleared by raising the adjustment ring 26 to a clear position,
thereby increasing the annular space 18 to allow the tramp to fall
or be pushed from the annular space 18.
To raise the adjustment ring 26 to a clear position, the illustrated
crusher 12 includes four hydraulic actuators 58 (FIG. 1) that can
be extended to push upward on the adjustment ring 26. The hydraulic
actuators 58 must provide sufficient force not only to lift the
weight of the adjustment ring 26 the bowl 24 and the bowl liner
20 but also to overcome the clamping force of the coil spring assembly
44 which force increases with compression of the springs 52. The
force required to raise the adjustment ring can be on the order
of about one and a half million (1500000) pounds or more. Such
high forces require high hydraulic pressures which can lead to blown
or leaking hoses.
In addition, there is a limit to the amount that the coil springs
52 can be compressed while raising the adjustment ring 26. This
limit is due not only to the spring forces of the assembly that
may exceed the maximum force that can be applied by the actuators
58 but also to the limits on compressibility of the coil springs
52 (i.e., the length of the fully compressed coil springs). As an
example, the above-described crusher 12 is designed to raise the
adjustment ring 26 only about two inches.
SUMMARY OF THE INVENTION
The invention is directed to improvements to cone crushers of the
above-described type. In one aspect, the invention includes a cone
crusher having a main frame, a first crusher member (e.g., a crusher
head) interconnected with the main frame, a second crusher member
(e.g., a crusher bowl and an adjustment ring) positioned adjacent
to the first crusher member, and a double-acting hydraulic lift
interconnected with both the main frame and the second crusher member.
The second crusher member is movable relative to the first crusher
member between an operating position and a clear position. The double-acting
hydraulic lift can include a cylinder, a manifold extending from
the cylinder, and an accumulator extending down from the manifold.
The invention also includes a cone crusher having a main frame,
a first crusher member (e.g., a crusher head) interconnected with
the main frame, a second crusher member (e.g., a crusher bowl and
an adjustment ring) positioned above the first crusher member, a
force transfer member interconnected with and extending downward
relative to the second crusher member, and a hydraulic spring having
an upper end interconnected with the main frame and a lower end
interconnected with the force transfer member. The second crushing
member is movable relative to the first crusher member between an
operating position and a clear position. The hydraulic spring provides
a downward clamp force on the force transfer member to compliantly
clamp the second crusher member to the main frame during crushing
operations. The cone crusher can further include a lower spring
segment interconnecting the lower end of the hydraulic spring with
the force transfer member. Preferably, the hydraulic spring comprises
a double-acting hydraulic lift. That is, the hydraulic spring preferably
provides the dual function of acting as a spring in one direction,
and acting as a lift in the opposite direction.
The invention further includes a cone crusher comprising a main
frame, a first crusher member interconnected with the main frame,
a second crusher member positioned adjacent to the first crusher
member, a hydraulic spring interconnected with both the main frame
and the second crusher member, and an elasto-viscous, resilient
pad operatively positioned between the hydraulic spring and the
main frame. The second crusher member is movable relative to the
first crusher member between an operating position and a clearing
position. The hydraulic spring provides a clamp force on the second
crushing member to compliantly clamp the second crusher member to
the main frame during crushing operations.
In one embodiment, the hydraulic spring is at least partially positioned
between first and second flanges of the main frame. Preferably,
a first resilient pad is positioned between the hydraulic spring
and the first flange, and a second resilient pad is positioned between
the hydraulic spring and the second flange. The hydraulic spring
may, for example, comprise a double-acting hydraulic lift.
The invention also includes a method of converting a mechanical
spring cone crusher to a hydraulic spring cone crusher. The mechanical
spring cone crusher includes a main frame, an adjustment ring, at
least one spring bolt, at least one mechanical spring, and at least
one lower spring segment. The method includes the steps of removing
the lower spring segment and the mechanical spring from the cone
crusher, securing (e.g., welding) the spring bolt to the adjustment
ring, positioning a hydraulic spring assembly adjacent to the main
frame, and securing the lower spring segment to both the hydraulic
spring assembly and the spring bolt.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a prior art cone crusher.
FIG. 2 is a side section view of the prior art cone crusher illustrated
in FIG. 1.
FIG. 3 is a perspective view of a cone crusher embodying the present
invention.
FIG. 4 is a top section view of the cone crusher illustrated in
FIG. 3 with the spring bolts removed.
FIG. 5 is an enlarged top view of the spring assembly illustrated
in FIG. 4.
FIG. 6 is a side section view taken along line 6--6 in FIG. 4 and
showing the hydraulic spring in the operating position.
FIG. 7 is the side section view of FIG. 6 with the hydraulic spring
in the clear position.
FIG. 8 is a side view of a spring assembly taken along line 8--8
in FIG. 4.
DETAILED DESCRIPTION
The present invention is embodied in the cone crusher 60 illustrated
in FIGS. 3-8. Similar to the prior art cone crusher 12 the cone
crusher 60 illustrated in FIGS. 3-8 includes most of the internal
components illustrated in FIG. 2. For example, although not specifically
illustrated, the cone crusher 60 includes a countershaft, a pinion,
a gear, a main shaft, a head, a mantle, a bowl liner and a bowl.
In addition, the cone crusher 60 includes (FIG. 3) an adjustment
ring 62 a main frame 64 spring bolts 66 and a hydraulic spring
assembly 68. Each of these components is described below in more
detail.
The adjustment ring 62 is threaded to the bowl of the cone crusher
60. As noted above, such threaded engagement allows height adjustment
of the bowl to achieve a range of spacing between the bowl liner
and the mantle. In its resting condition, the adjustment ring 62
butts against a frame seat 70 of the main frame 64.
The hydraulic spring assembly 68 of the illustrated embodiment
includes sixteen spring subassemblies, including twelve single-acting
subassemblies 90 and four double-acting subassemblies 92 (FIG. 4).
The single-acting subassemblies are operable to apply forces to
the adjustment ring 62 in only one direction (i.e., downward), while
the double-acting subassemblies can be operated to apply forces
to the adjustment ring 62 in two directions (i.e., both upward and
downward), as is described below in more detail.
Each spring subassembly (i.e., both single-acting and double-acting)
includes a cylinder member 94 and a piston member 96 slidably positioned
within the cylinder members 94. Each cylinder member 94 and corresponding
piston member 96 cooperatively define an upper chamber 98 and a
lower chamber 100 in the cylinder member 94 (FIG. 6). A manifold
member 102 (FIGS. 5 and 8) extends from each cylinder member 94
and interconnects the upper chamber 98 of each piston-cylinder arrangement
with an accumulator 108. The accumulator 108 provides compliant
pressure to the hydraulic fluid within the upper chamber 98 by providing
a bladder interface (not shown) between the hydraulic fluid and
a pressurized gas within the accumulator 108. The illustrated embodiment
utilizes a Bosch one gallon accumulator, available from the Robert
Bosch Fluid Power Corporation under part number 0 531 113 645 and
pressurized to an initial pressure of about 1800 psi.
As with the above-described prior art cone crusher 12 illustrated
in FIGS. 1 and 2 the cone crusher 60 includes spring bolts 66 extending
downward from the adjustment ring 62. Three spring bolts 66 are
associated with each single-acting subassembly and each double-acting
assembly. Each spring bolt 66 extends through the adjustment ring
62 with a spring bolt head 76 holding each spring bolt 66 in place
(FIGS. 3 and 6). The spring bolts 66 extend down from the adjustment
ring 62 and through a lower spring segment 78. Each spring bolt
66 further includes a lower nut 80 for holding the lower spring
segment 78 in place relative to the spring bolt 66.
The spring bolts 66 associated with the single-acting subassemblies
interconnect the adjustment ring 62 and the lower spring segment
78 as described above. The spring bolts 66 generally allow the lower
spring segment 78 to pull down on the adjustment ring 62 and further
allow the adjustment ring 62 to pull up on the lower spring segment
78 (FIG. 3). However, these spring bolts 66 neither facilitate the
lower spring segment 78 pushing up on the adjustment ring 62 nor
facilitate the adjustment ring pushing down on the lower spring
segment 78.
In contrast, the spring bolts 66 associated with the double-acting
subassemblies are secured to the adjustment ring 62 and the lower
spring segment 78 so as to allow the adjustment ring 62 and the
lower spring segments 78 to act on each other in both upward and
downward directions. In the illustrated embodiment, this is accomplished
by welding the corresponding spring bolt heads 76 and further by
proving 62 and further by providing upper nuts 86 immediately above
the lower spring segments 78 (FIGS. 6-8).
An upper fluid port 110 (FIG. 8) provides communication between
the upper chamber 98 and an external hydraulic circuit, as is described
below. In addition, each double-acting subassembly 92 further includes
a lower fluid port 112 for providing communication between the lower
chamber 100 and the hydraulic circuit, as described below in more
detail. In is this communication between the lower chamber 100 and
the hydraulic circuit that enables the double-acting subassembly
92 to act as a double-acting hydraulic lift (i.e., capable of acting
as a spring in one direction and a lift in the opposite direction).
The piston member 96 of each spring subassembly is interconnected
with the corresponding lower spring segment 78 such that upward
and downward movement of the piston member 96 causes upward and
downward movement of the lower spring segment 78 the associated
spring bolts 66 and the adjustment ring 62 and vice versa. In the
illustrated embodiment, each piston member 96 is butted against
the upper surface of the corresponding lower spring segment 78.
A piston bolt 114 is provided to secure each piston member 96 to
the corresponding lower spring segment 78.
The upper end of each cylinder member 94 is butted against an upper
frame flange 116 of the main frame 64 with a resilient upper pad
118 positioned therebetween. The upper pad 118 is secured to the
top of the cylinder member 94 utilizing an epoxy adhesive. The upper
pad 118 provides a flexible mounting that assists in maintaining
alignment between the cylinder member 94 and the piston member 96
during crushing operations, and further absorbs vibration during
crushing operations. More specifically, as noted above, when small
tramp is encountered during crushing operations, the adjustment
ring 62 will raise slightly to allow the tramp to pass. In reality,
only one side of the adjustment ring 62 raises, while the other
side remains seated, thereby placing the spring bolts 66 out of
alignment with the main frame. Such misalignment is transferred
to the piston member 96 through the lower spring segment 78 and
can result in misalignment between the piston member 96 and the
cylinder member 94 resulting in fluid leakage. By virtue of the
flexible mounting provided by the upper pad 118 the cylinder member
94 will remain aligned with the piston member 96 thereby inhibiting
fluid leakage. In addition, vibrational forces will be absorbed,
thereby extending component life.
Each of the four double-acting subassemblies 92 includes a support
structure 120 secured to the main frame 64. Each support structure
120 includes two support brackets 122 welded to the main frame 64
and a support flange 124 secured to the two support brackets 122.
The support flange 124 supports the lower end of the cylinder member
94 with a resilient lower pad 126 positioned therebetween. The lower
pad 126 helps to maintain alignment of the cylinder member 94 with
the piston member 96 while the adjustment ring 62 is raised to the
clear position, and further absorbs vibration, as is generally discussed
above with reference to the resilient upper pad 118. None of the
twelve single-acting subassemblies 90 includes a support structure
120 or a lower pad 126.
In the illustrated embodiment, the upper and lower pads 118 126
are made from a resilient laminated fabric pad sold under the trademark
Fabreeka, by Fabreeka International, Inc., and include an elastomeric
compound. The pads have a Shore A Durometer hardness of about 90
and a damping constant of about 0.14. The upper pad is about 25
mm thick and the lower pad is about 12.5 mm thick.
Referring to the schematic representation shown in FIG. 9 the
hydraulic circuit 130 of the illustrated embodiment includes a hydraulic
pump 132 a three position control valve 134 a counterbalance valve
136 a pilot operated check valve 138 a pressure switch 140 a
release orifice 142 a relief valve 144 an upper fluid line 146
a lower fluid line 148 a fluid tank 150 and a fluid filter 152.
The control valve 134 is movable between a neutral position (shown
in FIG. 8), an operating position, and a clear position. In the
neutral position, no pressure is supplied beyond the control valve
134.
During crusher operation, the control valve 134 is moved to the
operating position. In the operating position, the upper fluid line
146 is pressurized by the hydraulic pump 132 to thereby apply hydraulic
pressure to the upper chambers 98 of each spring subassembly. The
hydraulic pressure produces a downward force on each piston member
96 resulting in a downward force on the adjustment ring. Once the
pressure within the hydraulic circuit 130 reaches about 2000 psi,
the pressure switch 140 signals the hydraulic pump 132 to shut down.
Pressure of about 2000 psi is trapped between the check valve 138
and the upper chambers 98.
While crushing, the crusher may encounter non-crushable tramp and
consequently cause the adjustment ring to lift slightly from its
resting position. Such lifting of the adjustment ring causes the
piston members 96 to retract into the cylinder member 94 thereby
pushing fluid into the accumulators 108. Once the tramp has exited
the crusher, the accumulators 108 direct the oil back into the upper
chambers 98. If the system returns to less than 2000 psi, the pressure
switch 140 will signal the hydraulic pump 132 to start pumping to
bring the pressure back to 2000 psi. Whenever the hydraulic pump
132 is operating to re-pressurize the hydraulic circuit 130 an
audible alarm (not shown) is activated to notify the operator of
the crusher that hydraulic pressure was lost.
When tramp needs to be cleared from the crusher, the operator will
put the crusher in the clear mode with the control valve 134 in
the clear position. In this mode, hydraulic pressure to the upper
fluid line 146 is reduced to 5 psi due to the relief valve 144.
The back pressure maintained by the relief valve 144 insures contact
between the cylinder members 94 the upper pads, and the main frame
upper flange. Pressurized fluid is provided to the lower chambers
100 of the double-acting subassemblies via the lower fluid ports.
The result is that the four double-acting subassemblies will lift
the adjustment ring to the clear position. In addition, the piston
members 96 of the twelve single-acting subassemblies are forced
into the corresponding cylinder members 94. The release orifice
142 controls the speed at which the adjustment ring raises. In the
illustrated embodiment, the adjustment ring can be raised to about
5 inches.
After clearing the tramp, the system is returned to the operating
mode by moving the control valve 134 back to the operating position.
The counterbalance valve 136 is provided to prevent the adjustment
ring from slamming down onto the main frame due to its own weight
when the system is switched from the clearing mode to the operating
mode. More specifically, the counterbalance valve 136 is biased
to prevent pressure from leaving the lower chambers 100 of the double-acting
subassemblies until pressure exists in the upper chambers 98. This
feature also prevents the adjustment ring from slamming down onto
the main frame in the event of a hydraulic circuit failure.
The hydraulic cone crusher 60 described above with reference to
FIGS. 3-8 can be produced by modifying the prior art cone crusher
12 described above with reference to FIGS. 1 and 2. In this regard,
the spring bolts 54 spring nuts 56 lower spring segments 50 adjustment
ring 62 and upper frame flange 48 illustrated in FIGS. 1 and 2
are the same as the spring bolts 66 lower nuts 80 lower spring
segment 78 adjustment ring 62 and upper frame flange 116 illustrated
in FIGS. 3-8 except with the modifications noted below.
The modification of the prior art cone crusher 12 can be performed
as follows. Referring to FIGS. 1 and 2 with the lower spring segments
jacked up using a hydraulic jack (not shown), the three lower spring
nuts 56 are removed from each of the coil spring assemblies 44.
The jacks are subsequently lowered and the lower spring segments
50 are removed along with the coil springs 52. The lower surface
of the upper frame flange 48 is inspected to insure that it is smooth,
and the lower surface is ground if necessary. The two support brackets
122 (FIG. 6) are then welded to the main frame 64 and the double-acting
spring bolts 66 are welded to the adjustment ring 62. It should
be appreciated that the above-described welding operations could
be performed by any appropriate securing operation, such as pinning,
bolting, screwing, or any other suitable operation.
A hole is drilled in each lower spring segment 78 and the piston
bolt 114 is inserted through each hole and into the corresponding
piston member 96 to secure the piston member 96 to the corresponding
lower spring segment 78. The upper nuts 86 are threaded onto each
of the double-acting spring bolts 66. The lower spring segments
78 (and associated pistons and cylinders) are then positioned onto
the spring bolts 66 and the lower nuts 80 are installed. The four
double-acting subassemblies are then secured in place by screwing
the support flanges 124 to the corresponding support brackets 122.
Hydraulic hosing (not shown) is subsequently interconnected with
the upper fluid port 110 and lower fluid port 112. Finally, the
old alignment pins 31 are removed and replaced with new, longer
alignment pins (not shown) that extend above the adjustment ring
62 by about 75 mm when the adjustment ring 62 is in the operating
position. The new alignment pins 128 are longer to accommodate the
increased distance that the hydraulic spring assembly 68 raises
the adjustment ring 62. The old hydraulic actuators 58 are not utilized
on the modified cone crusher 60. Accordingly, the old hydraulic
actuators 58 can be removed or, alternatively, can be left in place
in an inactive state.
The foregoing description of the present invention has been presented
for purposes of illustration and description. Furthermore, the description
is not intended to limit the invention to the form disclosed herein.
Consequently, variations and modifications commensurate with the
above teachings, and the skill or knowledge of the relevant art,
are within the scope of the present invention. The embodiments described
herein are further intended to explain best modes known for practicing
the invention and to enable others skilled in the art to utilize
the invention in such, or other, embodiments and with various modifications
required by the particular applications or uses of the present invention.
It is intended that the appended claims be construed to include
alternative embodiments to the extent permitted by the prior art.
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