Abstrict A cone type crusher which has a crushing chamber constituted by
a crushing head assembly and a conical cap ring securely fitted
in a fixed frame, the crusher including an eccentric drive cylinder
for supportng therein and driving a vertical main shaft of the head
assembly for gyration. The eccentric drive cylinder is supported
by bearings which are located in two vertically spaced positions
to preclude frictional wear due to metallic contacts, and is vertically
movable for the purpose of adjusting the exit clearance of the crushing
chamber.
Claims What is claimed is:
1. A cone type crusher having a vertical main axis, said crusher
comprising:
(a) a barrel type outer frame;
(b) a cap ring mounted on said outer frame;
(c) an inner frame fixedly mounted on said outer frame;
(d) a drive shaft assembly fixedly mounted on said outer frame;
(e) a drive pinion rotatably driven by said fixedly mounted drive
shaft assembly;
(f) a horizontally disposed follower gear mounted in said inner
frame for rotation about the vertical main axis of the crusher and
in position to engage said drive pinion, said follower gear having
a plurality of radially inwardly projecting, vertically oriented
axial splines formed thereon;
(g) a drive cylinder mounted for vertical motion along the vertical
main axis of the crusher, said drive cylinder having a spline gear
formed thereon which engages said plurality of radially inwardly
projecting axial splines formed on said horizontally disposed follower
gear, said spline gear being sized and shaped to receive rotary
torque from said splines and to permit said drive cylinder to move
vertically relative to said follower gear at the same time that
said spline gear is receiving rotary torque from said splines;
(h) a cylindrical upper bearing which supports the upper portion
of said drive cylinder, said cylindrical upper bearing being located
radially outwardly of said drive cylinder and between said drive
cylinder and said inner frame;
(i) a cylindrical lower bearing which supports the lower portion
of said drive cylinder, said cylindrical lower bearing being located
radially inwardly of said drive cylinder and between said drive
cylinder and said outer frame;
(j) lift means for axially moving said drive cylinder along the
vertical main axis of the crusher at the same time that said spline
gear is receiving rotary torque from said splines, during which
vertical motion said drive cylinder slides vertically in both said
cylindrical upper bearing and said cylindrical lower bearing and
said spline gear slides vertically relative to said plurality of
radially inwardly projecting axial splines on said horizontally
disposed follower gear;
(k) a main crusher shaft generally vertically mounted in said drive
cylinder, said main crusher shaft being rotatable about an eccentric
axis disposed at a small angle relative to the vertical main axis
of the crusher;
(l) a crushing head mounted on said main crusher shaft in position
to define a crushing chamber in cooperation with said cap ring;
and
(m) an annularly shaped spherical thrust bearing disposed between
said crushing head and said drive cylinder radially outwardly of
said main crusher shaft,
whereby,
(n) when said lift means is activated to move said drive cylinder
vertically, there is relative axial movement between said horizontally
disposed follower gear and said spline gear, but the axis of rotation
of said drive pinion remains fixed;
(o) a moment on one side of said main crusher shaft produced by
an asymmetric load on said crushing head is offset by an opposite
moment acting through said annularly shaped spherical thrust bearing;
and
(p) said cylindrical upper and lower bearings reduce vibrations
of said drive cylinder to a minimum and distribute radial thrusts
produced by loads in said crushing chamber over a large contact
surface area.
2. A crusher as recited in claim 1 wherein said lift means comprise
a fluid piston and cylinder operatively disposed along the vertical
main axis of the crusher and bearing at one end against said drive
cylinder and the other end against said outer frame.
3. A crusher as recited in claim 1 and further comprising a main
bearing disposed between said main crusher shaft and said drive
cylinder.
4. A crusher as recited in claim 1 and further comprising a labyrinth
type lubrication seal operatively disposed between said inner frame
and said crushing head.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to cone type crushers.
More particularly, the invention concerns a bearing system for
a cone type crusher assembly which is supported on the underside
alone and free on its upper side, the bearing system preventing
irregular wear of bearings due to metallic contact resulting from
localized impact loads by means of cooperative action of vertically
distributed bearing structures and a spherical bearing structure
while in spite of its unique construction permitting free vertical
movements of the rotary crusher assembly even under torque transmitting
condition for adjustment of the exit clearance of the crushing chamber
in automatic operations.
2. Description of the Prior Art
As illustrated in FIGS. 1 and 2 the cone type crusher of this
sort generally includes a crusher support frame 1 with a fixed vertical
cylinder 34 at the center of its bottom portion, and an eccentric
drive cylinder 8 loosely fitted on the cylinder 34 and having a
follower gear 6 around its eccentric outer periphery to gyrate a
crusher assembly 20.
In such a crusher, it is the general practice not to support the
upper side of the crusher assembly 20 by a bearing and to provide
a bearing only between a bottom cylinder 35 of the crusher assembly
20 and the eccentric drive cylinder 8 for preventing the frictional
wear from being localized to the inner wall surface of the fixed
frame 1 under the influence of the feed material and by reason of
unhindered, very smooth feeding of the material. In this case, the
crushing load is imposed perpendicularly to the outer conical face
of the crusher assembly 20 and the load moment is received in the
direction in which the crusher 20 falls. Since the moment is received
solely by a bearing 36 which is provided at one position in the
conventional bearing structure as shown in the drawings, the cylindrical
surface of the bearing 36 is brought into metallic contact with
one side of the eccentric drive sleeve 8. As a result considerable
localized frictional wear takes place not only on the bearing 36
but also on the surface of the eccentric drive cylinder 8. This
detrimentally impairs the service life of the crusher and accelerates
deteriorations in its crushing ability particularly in a crusher
of the above-mentioned type which involves impact load and instrusion
of crushed dust during operation.
In addition, the crusher assembly 20 is provided with not only
a radial bearing but also a thrust bearing. In this connection,
the conventional practice has been to provide a spherical bearing
37 on top of a cylindrical main shaft 15 which is passed through
the eccentric drive cylinder 8. Therefore, the crushing load received
by the spherical bearing 37 imposes a bending moment on the main
shaft 15 or a main shaft bearing 16.
On the other hand, in order to cope with these problems, an attempt
has been made to lessen the concentration of load on the bearing
36 supporting the spherical bottom face of the crusher assembly
20 on the fixed frame 1 as shown in FIG. 3 thereby by generating
opposite resistant moment about the bearing 36. However, as seen
in that figure, this arrangement does not permit movement of the
main shaft 15 in the axial direction, and the upper portion of the
fixed frame 1 has to be rotatingly adjusted by screws in order to
adjust the exit clearance of the crushing chamber. It is therefore
impossible to adjust the exit clearance automatically during the
crushing operation. The adjustment of the exit clearance requires
stoppage of the operation and involves jobs which are very troublesome
and which take time and labor detrimentally to the efficient crushing
opeation. Further, the complicated construction is apparently disadvantageous
costwise.
SUMMARY OF THE INVENTION
The present invention has as its object the elimination of the
above-mentioned difficulties and problems. It is a more particular
object of the present invention to provide an improved bearing system
for a cone type crusher assembly, which is simple in construction
and permits adjustments of the exit clearance of the crushing chamber
during crushing operation.
According to the present invention, there is provided a cone type
crusher having a crushing chamber defined by a crushing head assembly
and a conical cave ring securely fitted in a fixed frame, the crusher
including an eccentric drive cylinder for supporting therein and
gyrating a vertical main shaft of the crushing head assembly; a
torque transmitting mechanism for gyrating the eccentric drive cylinder;
a lift mechanism for moving the eccentric drive cylinder up and
down in the axial direction thereof; bearing assembly located in
vertically spaced middle and lower positions on the fixed frame
for supporting the eccentric drive cylinder; and a spherical bearing
member provided between the top and bottom ends of the eccentric
drive cylinder and the crushing head assembly, respectively.
The above and other objects, features and advantages of the invention
will become apparent from the following description and the appended
claims, taken in conjunction with the accompanying drawings which
show by way of example a preferred embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 3 are diagrammatic sectional views of conventional cone
type crushers; and
FIG. 4 is a diagrammatic sectional view of a crusher embodying
the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 4 which shows a crusher according to the present
invention, indicated at reference number 1 is a barrel type fixed
frame forming an outer housing of the crusher and consisting of
a lower frame 2 and an upper frame 3 which is fixed on the lower
frame 2. The lower frame 2 is centrally provided with an inner housing
4 fixedly and coaxially with the outer housing about the center
(O) of the crusher, and receives at one side of its lower portion
a drive shaft assembly with a drive pinion 5 at the inner end thereof
and rotatable about a fixed axis.
Denoted by reference number 6 is a follower gear which is provided
on the bottom of the fixed frame 1 with its rotational axis in alignment
with the center of the crusher (O). The follower gear 6 is rotatably
supported by thrust and radial bearings and meshed with the drive
pinion 5 for rotation at a predetermined level.
A plurality of axially splines 7 formed on the inner periphery
of the follower gear 6 engage with a spline gear 9 which is formed
in the lower portion of the outer periphery of a cylindrical eccentric
drive cylinder 8 to permit relative axial movements of the latter.
The eccentric drive cylinder 8 is supported on the outer periphery
of its upper half portion by the inner housing 4 which is provided
with a cylindrical upper bearing 10 over the entire inner periphery
thereof.
Opposingly to the upper bearing 10 a cylindrical lower bearing
11 is fitted between a cylinder 12 which is integrally projected
from the bottom of the fixed frame 1 and a downwardly opened cylinder
8a forming the lower portion of the eccentric drive cylinder 8
the lower bearing 11 being substantially fixed to the cylinder 12.
The cylinder 12 slidably receives therein a piston 14 which is
movable up and down to adjust the position of the eccentric drive
cylinder 8. The lower portion of a main crusher shaft 15 is inserted
in the upper half portion of the drive cylinder 8 in a slightly
tilted position relative to the center of the crusher (O). The main
crusher shaft 15 is rotatable about its axis through a main bearing
16 on the outer periphery thereof.
The main crusher shaft 15 has a conical head center 17 fitted on
the outer periphery of its upper half portion and a mantle 18 integrally
held on the outer periphery of the head center 17 by a head lock
19 to form a crushing head assembly 20. The crushing head assembly
20 which opposes cone cap ring 21 on the inner periphery of the
upper frame 3 has no bearing at its free top end.
The crushing head assembly 20 is provided with a downwardly diverging
conical recess 22 on the underside thereof to receive the top end
of the eccentric drive cylinder 8 which is fixedly provided with
a spherical seat 23 of a concave ring type.
On the other hand, the bottom end of the crushing head assembly
20 terminates in a spherical face 20a which has its center at the
apex of the cone formed by the mantle 18.
In order to enhance the resistance to frictional wear of the upper
bearing 10 and other component parts, the inner housing 4 is provided
with a horizontal flange 24 beneath the crushing head assembly 20
the flange 24 having axial oil circulating holes 25 on its inner
periphery and mounting thereon a fixed outer cylinder 26 in the
form of double rings, a fixed intermediate cylinder 28 located spacedly
on the inner side of the outer cylinder 26 and having a communicating
port 27 and a fixed inner cylinder 29 located on the inner side
of the intermediate cylinder 28. These cylinders 26 28 and 29 which
form triple concentrical rings about the center of the crusher (O)
are tall and close enough to the crushing head assembly 20 to form
a liquid pool 30 of annular shape in plan view but allowing for
gyrating movement of the crushing head assembly 20. The pool 30
holds an ordinary liquid and receives between the outer and intermediate
cylinders 26 and 28 a cylinder 31 which extends downward from the
bottom end of the head center 17 of the crushing head assembly 20
concentrically with the center of inclination (O'), a substantial
portion of the cylinder 31 being rotatably dipped in the liquid
pool 30 to form a perfect bearing seal. Indicated at reference number
32 is lower seal, at reference number 33 an upper seal, and l denotes
the route of circulation of the bearing lubricating oil.
A crushing load F acting on the crushing head assembly 20 normally
produces a moment in the main shaft 15 according to the force F
to cause metallic contact to the main shaft bearing 16 by a one-sided
load. However, with the abovedescribed bearing system of the invention,
the one-sided loadcarrying phenomenon of the main shaft bearing
16 would not occur, since the moment M.sub.1 due to the force F
is offset by the opposite moment M.sub.2 which is generated through
the spherical seat 23 provided on top of the eccentric drive cylinder
8. In this connection, the conventional counterpart which has the
spherical seat on the main shaft 15 has been unable to eliminate
the onesided load carrying by the bearing.
The crushing load F itself is imposed through the eccentric drive
cylinder 8 to act on its outer periphery alone. The upper and lower
bearings 10 and 11 located in vertically spaced positions suppress
vibrations of the eccentric drive cylinder 8 to be kept to a minimum
and preclude the one-sided load-carrying phenomenon, in contrast
to the conventional crusher which has the main shaft bearing only
in one position. In addition, since the reaction force occurs not
only in the upper portion a but also in the distant lower portion
b, the pressure which is imposed on the respective bearings is very
small, that is to say, only a light force is supported by surface
contact with the respective bearings, with no possibilities of localized
frictional wear. Thus, the bearing system for the rotational operation
is entirely protected against the metallic contact due to one-sided
loading.
As is clear from the foregoing description, the present invention
contributes to enhance the durability of the bearing system in a
cone crusher and, by the employment of the liftable crushing head
assembly, it becomes possible to adjust the exit clearance of the
crushing chamber freely at any time, permitting automation of the
crushing operation.
Obviously, numerous modifications and variations of the present
invention are possible in light of the above teachings. It is therefore
to be understood that within the scope of the appended claims, the
invention may be practiced otherwise than as specifically described
herein. |