Abstrict A bearing retainer apparatus for a gyratory crusher is comprised
of a bearing having a ball, a shaft disposed within the ball, and
a plate secured to the shaft. Further, a method of assembling a
bearing retainer system for a gyratory crusher includes attaching
a bearing retainer plate onto the shaft of the crusher using bearing
retainer bolts such that the bearing is clamped onto the shaft.
Claims What is claimed is:
1. A bearing retainer apparatus in combination with a gyratory
crusher, comprising: a bearing including a ball; an upright shaft
disposed within the ball; and a plate attached to a top end of the
shaft, and configured to prevent the ball from moving upward on
the shaft; the ball being of hemispherical shape having a longer
horizontal dimension at an upper end thereof than at a lower end
thereof; the upper end of the ball including an annular lip disposed
between an underside of the plate and the top end of the shaft and
forming a gap therebetween; the plate extending horizontally outwardly
past an outer periphery of the top end of the shaft.
2. The bearing retainer apparatus of claim 1 wherein the ball is
a hemispherical ball.
3. The bearing retainer apparatus of claim 2 wherein the ball has
an annular lip extending between the shaft and the plate.
4. The bearing retainer apparatus of claim 1 wherein the plate
is about 2.4 inches thick, and has a radius of about 10.4 inches.
5. The bearing retainer apparatus of claim 1 wherein the plate
is made of steel.
6. The bearing retainer apparatus of claim 1 wherein the plate
is secured to the shaft by a plurality of bolts.
7. A gyratory crusher, comprising: a shell; an upright shaft disposed
within the shell; a spider coupled to the shell; a bearing disposed
within the spider, the bearing having a ball into which a top end
of the shaft extends; and a bearing retainer plate attached to the
top end of the shaft for clamping the ball to the shaft; the ball
being of hemispherical shape having a longer horizontal dimension
at an upper end thereof than at a lower end thereof; the upper end
of the ball including an annular lip disposed between an underside
of the plate and the top end of the shaft and forming a gap therebetween;
the plate extending horizontally outwardly past an outer periphery
of the top end of the shaft.
8. The gyratory crusher of claim 7 wherein the ball is a hemispherical
ball.
9. The gyratory crusher of claim 8 wherein the ball has a lip extending
between the shaft and the bearing retainer plate.
10. The gyratory crusher of claim 7 wherein the plate has a thickness
of about 2.4 inches and a radius of about 10.4 inches.
11. The gyratory crusher of claim 7 wherein the bearing retainer
plate is attached to the shaft by a plurality of bolts.
12. The gyratory crusher of claim 7 wherein the bearing retainer
plate is made of steel.
Description FIELD OF THE INVENTION
The present invention relates to rock crushing systems, such as
conical rock crushers or gyratory crushers. More specifically, the
present invention relates to a mainshaft bearing retainer for rock
crushers.
BACKGROUND OF THE INVENTION
Gyratory rock crushers generally have a downwardly expanding central
conical member which rotates or gyrates within an outer upwardly
expanding frustroconically shaped member typically called a shell.
The shell can be comprised of two or more pieces, e.g., a top shell
and a bottom shell. The central conical member generally has a wearing
cover or a liner called a mantle. A spider assembly rests on the
top shell, forming the top of the support structure for the machine.
A shaft extends vertically through the rock crusher. This shaft
is supported by a bearing in the spider assembly. The central portion
of the shaft tapers inwardly in an upward direction to form the
central conical crushing member. This portion of the shaft supports
the mantle, which moves with the shaft to effect the crushing operation.
The spider assembly is designed to support the shaft while allowing
gyratory movement during operation of the machine. Additionally,
the vertical position of the shaft is controlled by a piston arrangement
in the spider. The piston is slidably disposed within the spider.
A bearing is disposed within the piston, and supports the shaft
while allowing gyratory motion. The bearing has a hemispherical
ball disposed in a socket, lubricated by oil or grease. A mechanical
attachment system is required to clamp the ball to the shaft.
In previous designs, the ball has been secured to the shaft using
a fastener, such as a nut. The nut is threaded onto the shaft above
the ball, which in turn has a hydraulic system used to press the
ball onto the shaft. In this type of arrangement, the shaft must
extend through the ball to allow the nut to be threaded above the
ball. The nut is retained by a bracket system bolted to the top
of the shaft.
The conventional mechanical attachment systems are difficult and
costly to assemble, repair, and replace because of the complexity
of the arrangement. As described above, conventional systems use
a hydraulic system to press the ball onto the shaft during assembly
and a retainer system to prevent the nut from loosening on the shaft
during operation. Further, the threaded shaft is subject to high
stress in the area of its threads due to the weight of the shaft
and the gyratory motion during crusher operation. Repairs to the
shaft can be costly due to the expense of the shaft as well as the
expense of the down time necessary to make repairs.
In contrast to conventional bearing retainer systems, it would
be advantageous to have a bearing retainer arrangement that may
be easily assembled, removed, and replaced. Further, there is a
need for a bearing retainer system that does not require threads
on the exterior of the shaft of the gyratory crusher. Further still,
there is a need for a bearing retainer system that does not require
a hydraulic system to assemble the ball and the shaft.
SUMMARY OF THE INVENTION
An exemplary embodiment relates to a bearing retainer apparatus.
The bearing retainer apparatus is for a gyratory crusher. The bearing
retainer apparatus includes a ball, a shaft disposed within the
ball, and a plate configured to prevent the ball from moving upward
on the shaft. The plate is secured to the shaft.
Another embodiment relates to a gyratory crusher including a shell,
a shaft disposed within the shell, and a spider coupled to the shell.
A bearing having a ball is disposed within the spider, and a bearing
retainer plate clamps the ball to the shaft.
A still further embodiment relates to a method of assembling a
bearing retainer system for a gyratory crusher having a shaft and
a ball. The method includes steps of providing a bearing retainer
plate, providing a plurality of bearing retainer bolts, placing
the ball on the shaft, and attaching the plate to the shaft with
the bolts. The ball is clamped to the shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will hereafter be described with reference to the
accompanying drawings, wherein like reference numerals denote like
elements, and:
FIG. 1 is a vertical cross-sectional view of the gyratory crusher;
and
FIG. 2 is a more detailed cross-sectional view of the bearing and
retainer of a gyratory crusher.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 a gyratory crusher 10 can be utilized to crush
rock, ore, minerals, waste, or other material. Gyratory crusher
is assembled on a cast steel base or bottom shell 12 having a central
hub 14. Central hub 14 is provided with a vertical bore 18 adapted
to receive a cylindrical support shaft 20 and eccentric 24. This
shaft 20 varies in cross section, but extends through the machine
into the spider 46. Drive housing 13 extends outwardly from hub
14 to enclose a drive mechanism 22. Drive mechanism 22 causes rotation
of an eccentric 24 which directs the gyratory motion of the shaft
20.
A head assembly 26 which is part of the shaft 20 includes a head
member 30 which is covered by a mantle 34. Mantle 34 provides one
of the crushing surfaces of crusher 10.
A top shell 36 projects upwardly from bottom shell 12 and is covered
by a spider assembly including a spider 46. Alternatively, top shell
36 and bottom shell 12 can be a single piece component. Spider 46
receives an end 42 of shaft 20.
Top shell 36 is protected from wear by several rows of concaves
62. These concaves 62 provide the crushing surface opposing mantle
34. Spider 46 can be attached or rest upon top shell 36. Vertical
positioning of shaft 20 with respect to top shell 36 adjusts the
relative position of the mantle 34 of the head member 26 with respect
to concaves 62 thereby adjusting the size of the crushed material
exiting crusher 10.
Material to be crushed is supplied through spider 46 which includes
openings (not shown) for entry of the material into crushing cavity
50. A liquid flush apparatus (not shown) may be provided for spraying
a liquid such as water toward the crusher cavity 50.
The spider 46 is comprised of spider arms 52 radially extending
outward from the center to a spider rim (not shown). A spider cap
54 sits on the top center of the spider 46. Each of the spider arms
52 is protected from falling material by a spider arm guard 56.
The spider rim is protected by a rim liner (not shown), also known
as a hopper liner.
Shaft 20 is supported by a bearing 80 within spider 46. The bearing
80 is disposed within a piston 82 that travels vertically within
spider 46 to adjust the vertical positioning of shaft 20. The piston
82 is moved by means of a hydraulic system including a hydraulic
fluid inlet 84 and a hydraulic fluid ring 86 that is filled to
move piston 82 upward. A bearing retainer plate 92 is used to clamp
a bearing ball 81 to the shaft 20.
The bearing ball 81 is disposed within socket 90. It has a hemispherical
structure designed to receive top end 42 of shaft 20. The ball 81
has a radius of about thirteen inches and is lubricated by oil injected
between ball 81 and socket 90. An upper end of the ball has a longer
horizontal dimension D than a lower end thereof.
Referring now to FIG. 2 shaft 20 is supported within bearing 80
by a bearing retainer plate 92 and bearing retainer bolts 94. Bearing
retainer plate 92 is made of steel, has a diameter of about twenty-one
inches and is about two and one-half inches thick. Ball 81 has a
flat surface on top, upon which bearing retainer plate 92 may rest.
Bearing retainer plate 92 is attached to shaft 20 by bearing retainer
bolts 94.
In a preferred embodiment, a bearing lip 98 extends partially into
the space between shaft 20 and bearing retainer plate 92. The lip
98 has a thickness of about one inch and extends about one-half
inch inward from the perimeter of shaft 20. Thus, in a preferred
embodiment, the lip 98 has an inner diameter of about fourteen inches.
Because the diameter of the bearing retainer plate 92 is greater
than that of the inner diameter of the ball 81 the plate 92 overlays
ball 81 with an annular contact surface area of about 190 square
inches, having an inner diameter of fourteen inches and an outer
diameter of twenty-one inches.
In the preferred embodiment, the bearing retainer bolts 94 are
M30.times.120 mm steel bolts. There are preferably 10 bearing retainer
bolts 94 clamping the plate 92 to the shaft 20. There are no threads
on the shaft 20 at the interface 96 between ball 81 and shaft 20.
Threads are not necessary because shaft 20 is supported by bearing
retainer bolts 94.
The bearing retainer plate system precludes the need for a nut
threaded on shaft 20 to secure ball 81 to shaft 20. Because no nut
is used, no hydraulic system is necessary to apply assembly loads
between ball 81 and shaft 20. Instead, a clamping load and assembly
load are provided by bolts 94. The lack of threads on the exterior
of the shaft 20 reduces possible stresses on and resultant damage
to the shaft 20.
Bearing 80 must support shaft 20 while allowing gyratory motion.
These loads can be substantial as shaft 20 weighs twenty-four tons
in a preferred embodiment. The bolts 94 and bearing retainer plate
92 can be designed to support that load.
Additionally, bearing retainer bolts 94 resist loads due to the
gyratory motion of shaft 20. Shaft 20 is generally constructed of
steel, which may be threaded to allow bolts 94 to be attached. To
support the loads of shaft 20 during crusher 10 operation, the bolts
94 are threaded two inches into shaft 20 in the preferred embodiment.
In the preferred embodiment, bearing retainer plate 92 is easily
removed from shaft 20 and bearing 80 for repair and replacement.
This is an advantage over systems using a large nut to clamp ball
81 onto shaft 20 because systems using a large nut have an additional
hydraulic system as well as an apparatus required to prevent nut
from loosening during operation. Therefore, the present bearing
retainer plate device is superior to conventional designs with respect
to ease of installation and maintenance.
The gyratory crusher 10 operates as follows. When the drive mechanism
22 is driven by any appropriate means, it transmits power to the
eccentric 24. The eccentric 24 causes the gyration of the head assembly
26 resulting in the crushing of the material in the crushing chamber
50. The phantom lines flanking the mantle and center axis on FIG.
1 indicate the range of gyratory motion.
The above arrangement solves the longstanding problems discussed
in the Background of the Invention section because the exterior
of the shaft 20 does not require threads that increase stresses
on the shaft 20 and are susceptible to breakage and wear. Additionally,
the low cost and simplicity of the bearing retainer plate system
is superior to the complicated retaining systems of the prior art.
Finally, the bearing retainer plate 92 and bolts 94 may be more
easily removed and installed than prior systems. This allows for
more efficient maintenance and installation which results in lower
costs.
While several embodiments of the invention have been described,
it should be apparent to those skilled in the art that what has
been described is considered at present to be the preferred embodiments
of a bearing retainer system. However, in accordance with the patent
statutes, changes may be made in the design without actually departing
from the true spirit and scope of this invention. The following
claims are intended to cover all such changes and modifications
which fall within the true spirit and scope of this invention. |