Abstrict A hydraulically adjustable cone crusher and a axial bearing assembly
of a cone crusher, which crusher comprises an hydraulic adjustment
cylinder/piston assembly mounted in the space formed between the
crushing head and the upper surface of the main shaft for adjusting
the setting of the crusher. The pressure medium of the hydraulic
adjustment system of the crusher is supplied to the pressure medium
space formed, except by the adjustment cylinder/piston assembly,
also by at least one bearing element.
Claims 1. A hydraulically adjustable cone crusher comprising: a frame,
a main shaft mounted at its lower part immobile with respect to
the frame, an eccentric shaft mounted to be rotated about the central
axis of the main shaft, around the main shaft, a crushing head mounted
rotatably on the eccentric shaft, an inner crushing tool mounted
on the crushing head, an outer crushing tool mounted in the frame,
a crushing chamber formed between the outer and inner crushing tool
for crushing the feeding material, and an adjustment cylinder/piston
assembly of a hydraulic adjustment system of the crusher for defining
the vertical position of the crushing head with respect to the main
shaft, said adjustment cylinder/piston assembly being mounted in
the space formed between the crushing head and the upper surface
of the main shaft, characterized in that the pressure medium of
the hydraulic adjustment system of the crusher is supplied to the
pressure medium space formed, except by the adjustment cylinder/piston
assembly, also by at least one bearing element.
2. A crusher in accordance with claim 1 characterized in that
the number of the bearing elements is at least two.
3. A crusher in accordance with claim 2 characterized in that
between the surfaces of the lower axial bearing and the upper axial
bearing facing each other there is located at least one sealing
ring.
4. A crusher in accordance with claim 1 characterized in that
between the surfaces of the upper axial bearing and the adjustment
piston facing each other there is located at least one sealing ring.
5. A crusher in accordance with claim 1 characterized in that
between the surfaces of the upper axial bearing and the adjustment
cylinder facing each other there is located at least one sealing
ring.
6. A crusher in accordance with claim 1 characterized in that
the hydraulic pressure medium and the lubricant are of one and the
same material.
7. Axially arranged axial bearing assembly of a cone crusher adjusted
hydraulically, said axial bearing assembly comprising an upper axial
bearing and a lower axial bearing and at least one aperture for
supplying pressure medium through the axial bearing assembly, characterized
in that between the surfaces of the lower axial bearing and the
upper axial bearing facing each other there is located at least
one sealing ring.
8. Axial bearing assembly in accordance with claim 7 characterized
in that at least one sealing ring is located between the upper axial
bearing and the surface facing its upper surface.
9. Axial bearing assembly in accordance with claim 7 characterized
in that the sealing ring is at least partly mortised into at least
one of the surfaces facing each other.
10. Axial bearing assembly in accordance with claim 9 characterized
in that the sealing ring is provided with a flexing part.
11. A crusher in accordance with claim 2 characterized in that
between the surfaces of the upper axial bearing and the adjustment
piston facing each other there is located at least one sealing ring.
12. A crusher in accordance with claim 3 characterized in that
between the surfaces of the upper axial bearing and the adjustment
piston facing each other there is located at least one sealing ring.
13. A crusher in accordance with claim 2 characterized in that
between the surfaces of the upper axial bearing and the adjustment
cylinder facing each other there is located at least one sealing
ring.
14. A crusher in accordance with claim 3 characterized in that
between the surfaces of the upper axial bearing and the adjustment
cylinder facing each other there is located at least one sealing
ring.
15. A crusher in accordance with claim 2 characterized in that
the hydraulic pressure medium and the lubricant are of one and the
same material.
16. A crusher in accordance with claim 3 characterized in that
the hydraulic pressure medium and the lubricant are of one and the
same material.
17. A crusher in accordance with claim 4 characterized in that
the hydraulic pressure medium and the lubricant are of one and the
same material.
18. A crusher in accordance with claim 5 characterized in that
the hydraulic pressure medium and the lubricant are of one and the
same material.
19. Axial bearing assembly in accordance with claim 8 characterized
in that the sealing ring is at least partly mortised into at least
one of the surfaces facing each other.
Description BACKGROUND OF THE INVENTION
[0001] The present invention relates to cone crushers. More precisely,
the invention concerns a hydraulic setting adjustment system of
a cone crusher and an axial bearing assembly suitable for use in
the setting adjustment system of a cone crusher.
[0002] Known in the patent literature, as well as by those skilled
in the art, there are several different crushers, in which the crushing
of stones or corresponding hard materials is effected in a crushing
chamber defined by two crushing tools having substantially a form
of truncated circular cones. This kind of a crusher is called cone
crusher.
[0003] It is essential for the quality of the crushed final product
that the form of the crushing chamber does not change substantially
during the crushing procedure. Essential for the grain size of the
produced crushed aggregate is the so called setting of the crusher,
in other words, the minimum distance between the crushing tools
during a working cycle of the crusher. When the crushing tools wear,
the setting of the crusher will be, however, changed. In order to
compensate this change, different setting adjustment solutions have
been used in crushers already for a long time. Several solutions
of this kind are known in the patent literature as well as by those
skilled in the art. Many of those are hydraulically driven.
[0004] Finnish patent application FI-20040585 (Nieminen et al.)
discloses a hydraulically adjustable cone crusher, wherein a piston-cylinder
assembly of the hydraulic adjustment system is located in a space
between the upper end of the main shaft, attached immobile into
the frame, and the crushing head mounted movably with respect to
the frame around the upper end of the main shaft. In this way, a
crusher with small outer dimensions is provided without having to
compromise over the size of the crushing chamber and thereby over
the capacity of the crusher.
[0005] The publication discloses two different hydraulic adjustment
solutions, one of those having the adjustment piston as the lower
portion of the piston-cylinder pair and the other having the adjustment
piston as the upper portion of the piston/cylinder pair.
[0006] In accordance with said patent publication, the pressure
medium required for the setting adjustment of the crusher is supplied
to the pressure medium space of the hydraulic setting adjustment
cylinder via flexible hose in a lubricant channel extending inside
the main shaft of the crusher. In accordance with one embodiment
of said publication, the hose is attached at its upper end to an
extension of the lower end of the adjustment piston, said extension
extending through the axial bearing assembly of the crusher, and
said extension, as well as the piston itself include a channel for
supplying pressure medium through the piston into the pressure medium
space of the adjustment cylinder. In accordance with another embodiment
of said publication, the hose is attached at its upper end to an
extension of the lower end of the adjustment cylinder, said extension
extending through the axial bearing assembly of the crusher, and
said extension, as well as the bottom of the cylinder itself include
a channel for supplying pressure medium to the adjustment cylinder,
to the pressure medium space below the piston.
[0007] The hydraulic cylinder/piston assembly 12 13 of the setting
adjustment system of the crusher can naturally be arranged by means
of a hydraulic control circuit (not shown) of the crusher to operate
as a safety device in situations, where some uncrushable material,
for example solid metal, gets by mistake into the crushing chamber
of the crusher among the feed material. In this kind of situations,
the hydraulic cylinder-piston-assembly 12 13 can be arranged by
means of the control circuit to operate so, that when uncrushable
material gets into the crushing chamber and the hydraulic control
system discovers abnormal increase of the hydraulic pressure in
the pressure medium space of the setting adjustment system, pressure
medium will be discharged from the setting adjustment system in
order to decrease the pressure and to enlarge the setting of the
crusher, so that the uncrushable material can leave the crushing
chamber without causing any damage to the crusher. This kind of
an operation is known from the crushers of prior art, having a hydraulic
cylinder-piston assembly as a setting adjustment system. The solution
in accordance with said Finnish patent application FI-20040585 for
supplying adjustment pressure medium has certain weaknesses. The
construction is demanding for the pressure medium hose to be used.
It must withstand many kinds of stresses: bending, twisting, pulsating
changes of the pressure as well as fatigue loading caused by these
together and separately. Thus, these solutions turn out to be unreliable
in operation. In case the above-mentioned drawbacks should be eliminated
by the hose material choice, the solution will also be expensive.
[0008] One drawback of the solution is also the fact that a quite
large central aperture must be made to the lower bearing of the
axial bearing assembly for the extension of the lower end of the
adjustment piston or the adjustment cylinder, said extension extending
through the axial bearing assembly, for allowing the movement of
the extension when the crusher is in operation. In the solutions
in accordance with said patent application the adjustment piston
or adjustment cylinder with its lower end extension is an element
moving laterally with respect to the lower bearing of the axial
bearing assembly. The large central aperture means that the supporting
area of the bearing surfaces of the axial bearing assembly are quite
small compared to their total surface area, whereby the ability
of the crusher to bear vertical crushing loads remains small. This
means, in fact, decreasing capacity of the crusher.
[0009] For compensating the effect of the large central aperture,
the outer diameters of the bearing surface of the axial bearing
assembly should be increased, whereby also the outer dimensions
of the crusher itself are increased. This is not desirable.
SHORT DESCRIPTION OF THE INVENTION
[0010] For solving the problems of the prior art there is now invented
a hydraulically adjustable cone crusher in accordance with claim
1 and an axially arranged axial bearing assembly of the crusher
in accordance with claim 7.
[0011] In the solution in accordance with the present invention,
the pressure medium required for adjusting the setting of the crusher
is supplied to pressure medium channel included in the pressure
medium space of the adjustment cylinder, said pressure medium channel
extending from the lower axial bearing mounted to the upper end
of the main shaft of the crusher through a stiff pipe or hose included
in the lubricant channel going inside the main shaft of the crusher.
Thus, the pipe or the hose is not subject to movement and wearing
caused by that during the operation.
[0012] In the solution in accordance with the invention, more simple
solutions can be used for supplying the pressure medium to the pressure
medium space than in the described solutions of prior art. Thus,
the solution in accordance with the present invention is more durable,
more reliable and cheaper than the solution of prior art disclosed
in said Finnish patent application.
[0013] In the crusher in accordance with the invention, smaller
lead-through channels can be formed for the pressure medium into
the bearing surfaces of the axial bearing assembly, than those of
the prior art. Thereby a bigger bearing capacity of the axial bearing
assembly is provided, and, consequently, a bigger capacity of the
crusher.
[0014] In addition, the crusher in accordance with the invention
is more easily mountable and dismountable than the crusher known
in prior art.
[0015] More precisely, the crusher in accordance with the present
invention is characterized by what is stated in the characterizing
part of claim 1 and the axial bearing assembly in accordance with
the present invention is characterized by what is stated in the
characterizing part of claim 7.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be described in more detail in the following,
with reference to the enclosed drawings, wherein:
[0017] FIG. 1 shows as a cross-sectional view one cone crusher
of prior art,
[0018] FIG. 2 shows as a cross-sectional view another cone crusher
of prior art,
[0019] FIG. 3 shows as a cross-sectional view a cone crusher in
accordance with one embodiment of the present invention,
[0020] FIG. 4 shows an enlarged detail of the cone crusher of FIG.
3
[0021] FIG. 5 shows as a cross-sectional view a cone crusher in
accordance with another embodiment of the present invention,
[0022] FIG. 6 shows an enlarged detail of the cone crusher of FIG.
5
[0023] FIGS. 7 and 8 show details of some preferred embodiments
of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Main parts of the crushers of FIGS. from 1 to 6 are: [0025]
lower frame 1 [0026] upper frame 2 [0027] main shaft 3 [0028]
crushing head, i.e. support cone 4 [0029] outer crushing tool 5
[0030] inner crushing tool 6 [0031] crushing chamber 7 [0032]
eccentric shaft 8 [0033] gearwheel of the eccentric shaft 9 [0034]
outer radial bearing bushing 10 [0035] inner radial bearing bushing
11 [0036] adjustment cylinder 12 [0037] adjustment piston 13
[0038] protective bushing 14 [0039] lubricant channel 15 [0040]
supply hose for pressure medium 16 [0041] upper axial bearing 17
[0042] lower axial bearing 18 [0043] pressure medium space 19
[0044] dust sealing 20 [0045] pressure medium channel of the adjustment
piston 21 [0046] pressure medium channel of the adjustment cylinder
22 [0047] pressure medium supply pipe 31 [0048] lubricant channel
of the eccentric shaft 41 [0049] sealing ring of the axial bearing
assembly 42 [0050] sealing ring of the adjustment piston 43 [0051]
connector 44 [0052] pressure medium channel 45 [0053] lubricant
space 46 [0054] sealing ring of the adjustment cylinder 61 [0055]
groove of the sealing ring 71 [0056] sealing part of the sealing
ring 81 [0057] flexing part of the sealing ring 82.
[0058] In FIGS. 1 2 3 and 5 the setting of the crusher is marked
with s.
[0059] The frame of the crusher shown in FIGS. 1 and 2 is formed
from two main units: the lower frame 1 and the upper frame 2. The
outer crushing tool 5 attached to the upper frame and the inner
crushing tool 6 attached to the main shaft 3 via crushing head,
in other words via support cone 4 form the crushing chamber 7
to which the material to be crushed is fed from above the crusher.
[0060] The main shaft 3 of the crusher is attached immobile to
the lower frame of the crusher. The eccentric shaft 8 is attached
to the main shaft rotatably, rotated by the driving device (not
shown) and the power transmission (for purpose of simplifying also
not shown) via gear wheel 9. The central axis of the central aperture
of the eccentric shaft 8 is with respect to the central axis of
the outer surface of the eccentric shaft inclined or parallel on
a different axis. When the crusher is operating and the eccentric
shaft rotating about the central axis of the main shaft 3 of the
crusher, around the main shaft 3 the crushing head 4 mounted rotatably
on the eccentric shaft, gets in a horizontal oscillating or gyratory
motion with respect to the frame 1 of the crusher and the main shaft
3.
[0061] More precisely, the inclination of the inner aperture of
the eccentric shaft 8 here means that the central axis of the inner
aperture of the eccentric shaft is inclined with respect to the
central axis of the outer surface of the eccentric shaft.
[0062] Bearing bushings 10 11 are usually used between the main
shaft 3 of the crusher and the eccentric shaft 8 and between the
eccentric shaft and the crushing head 4. The horizontal crushing
forces exerted to the crushing head 4 are transmitted to the frame
1 of the crusher via the main shaft 3 the eccentric shaft 8 and
the bearing bushings 10 11 eventually used between the same.
[0063] In the space defined by the crushing head 4 and the main
shaft 3 of the crusher, there is provided a space for the hydraulic
cylinder/piston assembly 12 13 of the hydraulic setting adjustment
and safety system of the crusher. The vertical crushing forces exerted
by the crushing to the crushing head 4 are transmitted to frame
1 of the crusher by the crushing head via adjustment cylinder 12
and adjustment piston 13 and via pressure medium in the pressure
medium space 19 remaining between them, as well as via axial bearing
assembly 17 18 of the crusher. The axial bearing assembly comprises
usually two axial bearings, namely upper axial bearing 17 and lower
axial bearing 18 arranged slidably with respect to each other,
the respective contacting surface between them forming the sliding
surface, i.e. bearing surface of the axial bearing assembly.
[0064] The setting s of the crusher is reducingly adjustable by
pumping pressure medium to the pressure medium space 19 of the hydraulic
cylinder/piston assembly 12 13 of the hydraulic setting adjustment
and safety system. Correspondingly, the setting s of the crusher
is increasingly adjustable by discharging pressure medium from the
pressure medium space 19. A combined pressurizing and lubricating
device of the crusher (not shown), known in the art, is preferably
used as a pressure source.
[0065] A protective bushing 14 can be used on the surface of the
space formed for the adjustment cylinder 12 and piston 13 in the
crushing head in order to protect the crushing head from wearing.
[0066] The essential difference between the crushers of FIGS. 1
and 2 representing the prior art is how 'the adjustment cylinder
12 and the adjustment piston 13 are disposed with respect to each
other. In the crusher in accordance with FIG. 1 the adjustment
piston 13 rests on the main shaft, supported by the axial bearing
assembly 17 18. In the crusher in accordance with FIG. 2 the adjustment
cylinder 12 rests on the main shaft, supported by the axial bearing
assembly.
[0067] In the crusher in accordance with FIG. 1 a pressure medium
channel 21 is formed inside the adjustment piston 13 for leading
the pressure medium through it to the pressure medium space 19 of
the hydraulic cylinder/piston assembly 12 13 of the hydraulic setting
adjustment and safety system of the crusher. The pressure medium
channel of the adjustment piston forms a pipe-like extension to
the lower end of the piston 13 extending through the upper and
lower axial bearing 17 18 of the axial bearing assembly and being
connected at its lower end to the supply hose 16 of the pressure
medium extending inside the lubricant channel 15. Because the adjustment
piston moves in operation together with the crushing head 4 laterally
with respect to the frame, the central aperture of the lower axial
bearing 18 has been made large, so as to allow the motion of the
pipe-like extension of the lower end of the piston 13. A drawback
of this solution is that the supporting area of the bearing surfaces
of the axial bearing assembly 17 18 remains quite small with respect
to their total surface area, whereby the ability of the crusher
to receive vertical crushing forces remains small. This means, in
practice, decreasing capacity of the crusher. Compensation of the
effect of the large central aperture, again, requires, that the
outer diameters of the bearing surfaces of the axial bearing assembly
must be increased, whereby also the outer dimensions of the crusher
increase. This is not desirable.
[0068] Further, because the adjustment piston moves in operation
together with the crushing head 4 laterally, a flexible hose 16
must be used as a supply line for the pressure medium. The construction
is demanding for the pressure medium hose to be used. It must withstand
many kinds of stresses: bending, twisting, pulsating changes of
the pressure as well as fatigue loading caused by these together
and separately. Thus, these solutions turn out to be unreliable
in operation. In case the above-mentioned drawbacks should be eliminated
by the hose design, construction and material choices, the solution
will also be expensive.
[0069] In the crusher in accordance with FIG. 2 the supply of
the pressure medium to the pressure medium space 19 of the hydraulic
cylinder/piston assembly 12 13 of the hydraulic setting adjustment
and safety system of the crusher through the upper and lower axial
bearing 17 18 of the axial bearing assembly is arranged nearly
in the same way as in the crusher of FIG. 1. The difference is only
that in the crusher of FIG. 2 the pressure medium channel 22 is
formed into the adjustment cylinder 12. In this case the pressure
medium channel of the adjustment cylinder forms into the lower end
of the cylinder 12 a pipe-like extension extending through the upper
and lower axial bearing 17 18 of the axial bearing assembly to
be connected at its lower end to the pressure medium supply hose
16 extending inside the lubricant channel 15. In the crusher of
FIG. 2 the adjustment cylinder 12 moves in operation together with
the crushing head 4 laterally with respect to the frame of the crusher,
whereby also in this case the central aperture of the axial bearing
18 has been made large, so as to allow the motion of the pipe-like
extension of the lower end of the cylinder 12. For the pressure
medium supply hose 16 this solution sets the same requirements as
the solution of FIG. 1.
[0070] FIG. 3 shows as a cross-sectional view a cone crusher in
accordance with one embodiment of the present invention, and FIG.
4 shows point A of the cone crusher of FIG. 3 as an enlarged view.
The essential difference of the embodiment of the invention shown
in FIGS. 3 and 4 with respect to the closest embodiment of prior
art shown in FIG. 1 is how the supply of the pressure medium is
provided through the axial bearing assembly 17 18 to the pressure
medium space 19 of the hydraulic cylinder/piston assembly 12 13
of the hydraulic setting adjustment and safety system of the crusher.
The pressure medium channel 21 of the adjustment piston 13 does
not form any pipe-like extension to the lower end of the piston.
The pressure medium supply pipe 31 is not connected at its upper
end to the adjustment piston, but to the lower axial bearing 18
of the axial bearing assembly 17 18. A pressure medium channel
45 is formed into the adjustment piston 13 and the axial bearing
assembly 17 18 as a series of simple apertures opening to each
other so, that no extensions that would extend from one part to
another have been formed to the piston 13 or to either of the axial
bearings 17 18. Thus, the pressure medium space of the solution
in accordance with the invention is formed, except by the pressure
medium space 19 of the hydraulic cylinder/piston assembly, by the
apertures in the axial bearings 17 and 18 in other words, the pressure
medium channels 45.
[0071] The pressure medium channel 45 is separated from the lubricant
space 46 by means of a sealing ring 42 of the axial bearing assembly,
to keep the pressurized pressure medium inside the channel so, that
pressure medium cannot be discharged significantly from the pressure
medium channel to the lubricant space 46 and that the adjustment
pressure in the pressure medium space 19 cannot be decreased and
the setting of the crusher correspondingly increased. The sealing
ring 42 also prevents the pressure medium and lubricant from mixing
with each other significantly, although the invention is preferably
implemented so that the pressure medium and the lubricant are of
the same material, whereby minor leakage of the pressure medium
from the pressure medium space 45 to the lubricant space 46 is not
significant.
[0072] In the embodiment of the invention in accordance with FIGS.
3 and 4 the pressure medium channel 45 is additionally separated
from the lubricant space 46 with a sealing ring 43 of the adjustment
piston for preventing the pressure medium from discharging from
the pressure medium channel between the adjustment piston 13 and
the upper axial bearing 17.
[0073] The function of the lubricant channel 15--including the
lubricant space 46 inside the crushing head 4--is to lead lubricant
onto the sliding surfaces of the crusher, located at least between
the main shaft 3 and the eccentric shaft 8 between the eccentric
shaft and the crushing head 4 between the adjustment piston 13
and the main shaft 3 on the surfaces of bearing elements 10 11
17 18 attached to these, on the surfaces of the dust sealing arrangement
20 and on the surfaces of the gear wheel 9 of the eccentric shaft
and the power transmission (not shown). The lubricant channels 15
comprise in addition the apertures (not shown) formed to the lower
axial bearing 18 allowing the lubricant to penetrate to the sliding
surfaces of the axial bearing assembly 17 18 as well as the lubricant
channel 41 at the eccentric shaft allowing the lubricant to get
from the lubricant space 46 to the gearwheel 9 of the eccentric
shaft, to the power transmission of the crusher and to the dust
sealing 20.
[0074] It is clear to those skilled in the art, that the invention
is in no way limited to any definite number of the bearing elements
17 18 or sealing rings 42 43 of the axial bearing assembly. The
invention can also be implemented for example so that the adjustment
piston 13 and the upper axial bearing 17 are formed from one and
the same part, whereby the sealing 43 is not needed. It must also
be understood, that when the number of the bearing elements 17
18 on top of each other is increased, also at least as many seals
are needed as there is the number of slide surfaces between the
bearing elements. Further, it is clear that also two or more sealing
rings with different diameters within each other can be located
between the bearing surfaces.
[0075] As there is no extension in the adjustment piston extending
through the sliding surface of the axial bearing assembly 17 18
the apertures of the pressure medium channel formed to the axial
bearing assembly can be dimensioned smaller than in the crushers
known in the art. Thus, a larger supporting area of the bearing
elements can be reached with smaller total diameter of the bearing
elements, than in the crushers of prior art. In the dimensioning
of the apertures of the pressure medium channel 45 it is essential
to take into account the length of the stroke of the crusher caused
by the eccentric arrangement of the eccentric shaft 8 that is the
maximum shift of the bearing elements laterally with respect to
each other. The apertures must be dimensioned so that the pressure
medium channel 45 remains open in all situations to make the apertures
of the channel to open to each other.
[0076] The length of the stroke must also be taken into account
when dimensioning the sealing rings 42 43 in connection with the
pressure medium channel. It is essential, that the sealing rings
set in every working condition between the bearing surfaces, and
not for example at the apertures of the pressure medium channel
or outside a bearing surface of any bearing element 17 18.
[0077] The connection between the pressure medium supply pipe 31
and the lower axial bearing 18 can be implemented demountably with
a connector 44. As the lower axial bearing does not move substantially
with the adjustment piston 13 with respect to the frame 1 of the
crusher and thus with respect to the pressure medium supply pipe
31 when the crusher is in operation, prominently smaller stresses
are exerted to the pressure medium supply pipe than in the known
crushers of prior art. In the embodiment of the invention in accordance
with FIGS. 3 and 4 the construction, design and material of the
pressure medium supply pipe can be chosen much more freely than
in the crushers of prior art. For example a simple metallic or plastic
pipe commercially available or a usual hydraulic hose or pipes made
of different layer materials or composite constructions can be used
as supply pipe.
[0078] Preferably the upper axial bearing 17 and the adjustment
piston 13 are demountably attached to the crushing head 4 of the
crusher so, that when mounting and demounting the crusher, all said
three parts can be lifted to the crusher/from the crusher as one
assembly.
[0079] FIG. 5 shows as a cross-sectional view a cone crusher in
accordance with another embodiment of the present invention, and
FIG. 6 shows an enlarged detail of point B of the cone crusher of
FIG. 5.
[0080] The essential difference of the embodiment of the invention
shown in FIGS. 5 and 6 with respect to the embodiment shown in FIGS.
3 and 4 is how the adjustment cylinder 12 and the adjustment piston
13 are arranged with respect to each other. In the crusher of FIGS.
3 and 4 the adjustment piston 13 rests on the main shaft of the
crusher, supported by the axial bearing assembly. In the crusher
in accordance with FIGS. 5 and 6 the adjustment cylinder 12 rests
on the main shaft of the crusher, supported by the axial bearing
assembly.
[0081] The essential difference of the embodiment of the invention
shown in FIGS. 5 and 6 with respect to the closest embodiment of
prior art shown in FIG. 2 is how the supply of the pressure medium
is provided through the axial bearing assembly 17 18 to the pressure
medium space 19 of the hydraulic cylinder/piston assembly 12 13
of the hydraulic setting adjustment and safety system of the crusher.
The pressure medium channel 22 of the adjustment cylinder 12 does
not form any pipe-like extension to the lower end of the piston.
The pressure medium supply pipe 31 is not connected at its upper
end to the adjustment cylinder, but to the lower axial bearing 18
of the axial bearing assembly 17 18. A pressure medium channel
45 is formed into the adjustment cylinder 12 and the axial bearing
assembly 17 18 as a series of simple apertures opening to each
other so, that no extensions that would extend from one part to
another have been formed to the cylinder 12 or to either of the
axial bearings 17 18. Thus, the pressure medium space of the solution
in accordance with the invention is formed, except by the pressure
medium space 19 of the hydraulic cylinder/piston assembly, also
by the apertures in the axial bearings 17 and 18 in other words,
the pressure medium channels 45.
[0082] The pressure medium channel 45 is separated from the lubricant
space 46 by means of a sealing ring 42 of the axial bearing assembly,
that keeps the pressurized pressure medium inside the channel so,
that pressure medium cannot be discharged significantly from the
pressure medium channel to the lubricant space 46 and that the
adjustment pressure in the pressure medium space 19 cannot be decreased
and the setting of the crusher correspondingly increased. The sealing
ring 42 also prevents the pressure medium and lubricant from mixing
with each other significantly, although the invention is preferably
implemented so that the pressure medium and the lubricant are of
the same material, whereby minor leakage of the pressure medium
from the pressure medium space 45 to the lubricant space 46 is not
significant.
[0083] In the embodiment of the invention in accordance with FIGS.
5 and 6 the pressure medium channel 45 is additionally separated
from the lubricant space 46 with a sealing ring 61 of the adjustment
cylinder for preventing the pressure medium from discharging from
the pressure medium channel between the adjustment cylinder 12 and
the upper axial bearing 17.
[0084] The function of the lubricant channel 15--including the
lubricant space 46 inside the crushing head 4--is to lead lubricant
onto the sliding surfaces of the crusher, located at least between
the main shaft 3 and the eccentric shaft 8 between the eccentric
shaft and the crushing head 4 between the adjustment cylinder 12
and the main shaft 3 on the surfaces of bearing elements 10 11
17 18 attached to these, on the surfaces of the dust sealing arrangement
20 and on the surfaces of the gear wheel 9 of the eccentric shaft
and the power transmission (not shown). The lubricant channels 15
comprise, in addition, the apertures (not shown) formed to the lower
axial bearing 18 allowing the lubricant to penetrate to the sliding
surfaces of the axial bearing assembly 17 18 as well as the lubricant
channel 41 allowing the lubricant to get from the lubricant space
46 to the gear wheel 9 of the eccentric shaft, to the power transmission
of the crusher and to the dust sealing 20.
[0085] It is clear to those skilled in the art, that the invention
is in no way limited to any definite number of the bearing elements
17 18 or sealing rings 42 61 of the axial bearing assembly. The
invention can also be implemented for example so that the adjustment
cylinder 12 and the upper axial bearing 17 are formed from one and
the same part, whereby the sealing 61 is not needed. It must also
be understood, that when the number of the bearing elements 17
18 on top of each other is increased, also at least as many seals
are needed as there is the number of slide surfaces between the
bearing elements. Further, it is clear that also two or more sealing
rings with different diameters within each other can be located
between the bearing surfaces.
[0086] As there is no extension in the adjustment cylinder that
would extend through the sliding surface of the axial bearing assembly
17 18 the apertures of the pressure medium channel formed to the
axial bearing assembly can be dimensioned smaller than in the crushers
known in the art. Thus, a larger supporting area of the bearing
elements can be reached with smaller total diameter of the bearing
elements, than in the crushers of prior art. In the dimensioning
of the apertures of the pressure medium channel 45 it is essential
to take into account the length of the stroke of the crusher caused
by the eccentric arrangement of the eccentric shaft, that is the
maximum shift of the bearing elements 17 18 laterally with respect
to each other. The apertures must be dimensioned so that the pressure
medium channel 45 remains open in all situations to make the apertures
of the channel to open to each other.
[0087] The length of the stroke must also be taken into account
when dimensioning the sealing rings 42 61 in connection with the
pressure medium channel. It is essential, that the sealing rings
set in every working condition between the bearing surfaces, and
not for example at the apertures of the pressure medium channel
or outside a bearing surface of one bearing element 17 18.
[0088] The connection between the supply pipe 31 and the lower
axial bearing 18 can be implemented demountably with a connector
44. As the lower axial bearing does not move substantially with
the adjustment cylinder 12 with respect to the frame 1 of the crusher
and thus with respect to the pressure medium supply pipe 31 when
the crusher is in operation, prominently smaller stresses are exerted
to the pressure medium supply pipe than in the known crushers of
prior art. In the embodiment of the invention in accordance with
FIGS. 5 and 6 the construction, design and material of the pressure
medium supply pipe can be chosen much more freely than in the crushers
of prior art. For example a simple metallic or plastic pipe commercially
available or a usual hydraulic hose or pipes made of different layer
materials or composite constructions can be used as supply pipe.
[0089] Preferably the upper axial bearing 17 and the adjustment
cylinder 12 and the adjustment piston 13 are demountably attached
to the crushing head 4 of the crusher so, that when mounting and
demounting the crusher, all said four parts can be lifted to the
crusher/from the crusher as one assembly.
[0090] For the functionality of the invention it is essential,
that the construction, form and material of the sealing rings 42
43 61 are correctly chosen. The sealing rings must maintain their
sealing properties in especially demanding circumstances.
[0091] The sealing is exposed to the pressure of the pressure medium
of the hydraulic setting adjustment and safety system of the crusher,
said pressure being during the crushing operation usually from 7
to 15 MPa, in over-load situations momentarily even 40 MPa. To have
a proper sealing capacity against the pressure of the pressure medium,
the pressing force between the sealing ring and its stop face must
be suitable for the application. For those skilled in the art, it
is clear, that the sealing material 42 and the material of the stop
face 17 18 must be chosen so that their unreasonable mutual wearing
can be avoided. The point is that the bearing surface 17 18 must
wear as much at a point where the sealing ring 42 is against it,
as at a point, where, instead of the sealing ring 42 another bearing
surface 17 18 is against it.
[0092] The temperature of the pressure medium rises during the
crushing usually to 330-370 Kelvin degrees. In an overload situation
of the crusher the temperature in the axial bearing assembly 17
18 and accordingly also in the sealing rings 42 43 61 can momentarily
and locally rise much higher, even to 470 Kelvin degrees. Correspondingly,
the temperature of a crusher standing in winter conditions can go
very low, for example to 240 Kelvin degrees. Consequently, the wear
hardness, friction and elasticity properties of the sealing rings
42 43 61 must remain as even as possible in the temperature changes
of the sealing rings.
[0093] The material or materials of the sealing ring must naturally
be also from the point of view of their chemical properties suitable
for use in each application together with the appropriate pressure
medium and lubricant. In addition, a low friction coefficient is
required from the sealing material when it cooperates with the sliding
surface. Further, the effect known to those skilled in the art as
"stick-slip-effect" must not occur significantly between
the sealing material and its sliding surface.
[0094] The axial bearing pair 17 18 is formed of two metals with
different hardness. Usually, one bearing element of the pair is
made of steel and the other of bronze. This must be taken into account
when choosing the material of the sealing ring.
[0095] The material of the sealing ring can be chosen based on
the requirements set above, for example among commercially available
sealing materials. Especially suitable materials for the seals are
polymer materials, especially thermoplastic materials designed for
sealing use.
[0096] FIG. 7 shows a structural solution of a sealing ring 42
in accordance with one preferred embodiment of the invention. The
sealing ring 42 sets itself into a groove 71 formed into the bearing
element 18. Preferably the cross section of the sealing ring is
formed so, that when it sets itself into the groove 71 it is pressed
strongly between the bottom of the groove and the bearing surface
of the axial bearing 17 facing it. As an example of this kind of
a cross section of the seal 42 FIG. 7 shows a cross section of
a sealing ring having substantially a V form. The peak of the V
bottom is pressed strongly to the bottom of the groove 71 and the
upper peaks of the V are pressed strongly against the stop face
of the sealing ring.
[0097] FIG. 8 shows a structural solution of a sealing ring 42
in accordance with one preferred embodiment of the invention. The
sealing ring 42 is comprised of at least two parts with different
properties, of a sealing part 81 of the sealing ring and of a flexing
part 82 of the sealing ring, being made of different materials or
having a different structure. Purpose of the flexing part 82 is
to secure the optimal pressing force of the sealing ring 42 and
its stop face and thus to secure the best possible sealing performance
and wearing property, in other words, service life. Purpose of the
sealing part 81 is to secure the best possible wearing property
of the sealing ring 42 and its stop face and thus the best possible
sealing performance.
[0098] The flexibility of the sealing part 82 can be based except
on the properties of the material of the flexing part, also on its
mechanically flexible structure. The flexing part 82 can thus be
for example of appropriate rubber. Alternatively, the flexing part
82 can also be of solid metal, having, anyway, a mechanically flexible
structure.
[0099] It is clear for those skilled in the art, that the invention
is in no way limited to any definite location of the sealing ring
42 43 61 and the groove 71 for it. The groove for the sealing
ring can be formed into any element 12 13 17 18 forming the pressure
medium space 45 or into the stop face thereof. Correspondingly,
the sealing ring 42 43 61 can be located to any groove for sealing
ring of an element 12 13 17 18 forming the pressure medium channel
so, that the sealing ring and its stop face together form a pair
of sealing faces.
[0100] The power transmission left out of the FIGS. 1 2 3 and
5 for emphasizing the essential features of the invention can be
of a usual type known in the art. This kind of power transmission
solutions have been disclosed for example in the Finnish patent
application No. 20031509.
[0101] The invention is not limited to any definite pressure medium
or lubricant. Preferably the pressure medium and lubricant are of
one and the same material, for example of commercially available
hydraulic oils known in the art.
[0102] It is clear for those skilled in the art, that the invention
is suitable for crushing of stone or other hard mineral materials,
like ore or gravel, but not limited to those. It is also clear,
that the cone crusher in accordance with the invention can be used
for crushing of many other kinds of feed material, such as recyclable
construction waste like brick, concrete and asphalt, for crushing
of coke or glass, as well as for crushing of other hard materials
having same kind of physical properties as the mineral materials.
[0103] It is clear for those skilled in the art, that the invention
can also be implemented so that the pressure medium needed for the
adjustment of the crusher and the lubricant needed for the lubrication
of the crusher will change their supply channels with each other.
The invention can also be implemented so that there is a pressure
medium channel formed into the main shaft of the crusher, a separate
hose or pipe being provided inside said pressure medium channel
for supplying the lubricant needed for the lubrication of the crusher.
[0104] Further, it is clear for those skilled in the art, that
in the embodiment of FIG. 5 the adjustment piston 13 can be formed
into the crushing head 4 itself so, that no separate adjustment
piston is needed. |