Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The present invention relates to a crushing apparatus
having a centrifugal classiEier in which material of different ~ ~
kinds to be crushed are crushed by hammer means and the crushed
material is classified into coarse ~agr,~ents and fine fragments,
of which the fine fragments are selectively discharged from the
apparatus in succession.
Generally, when a material is crushed by rotating hammer
means, it is not always wholly crushed into fine fragments in
uniformity by the hammer means within a short time. ~ccordingly,
it is necessary to classify the crushed fragments according to the
size and to crush the coarse fragments with the hammer means again.
~ccordingly, the conventional process is such that the
makerial fed into the crushing appara-tus is crushed by hammer means,
clnd all oE its crushed fragments are discharged outside the
crushing apparatus to be classified according to the size by a
separately provided classifying apparatus. Thereafter, the coarse
fragments alone are returned to the crushing apparatus to be
crushed again. In the course of such repeated operation the fine
fragments are selectively taken out.
However, the conventional process as described above
requires, apart from the power for rotating the hammer means of the
crushing apparatus, the power for operating the classifying
apparatus and, after classification, returning the coarse frag-
ments to the crushing apparatus.
Thus, the overall apparatus not only tends to be large
and complex but entails a considerable power waste; its operation
is not economical.
The present invention eliminates the foregoing drawbacks
by making full use of the functions of the hammer means and provide :
an economical crushing apparatus equipped with a centrifugal
classifier which is capable of efficiently performing both
crushing and classifying operations. `~;
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According to the present invention there is provided a
crushing apparatus having a centrifugal classifier comprising: a
first housing and a second housing substantially coaxial with each
other; first conduit means and second conduit means for communica- ~ .
ting the first housing and the second housing, the first conduit
means being connected to both the housings at a position proximate
to the peripheral walls thereof and having an annular cross sec-
tion, the second conduit means being connected to both the
housings at a position closer to the axis of the housings than the
10 first conduit means; hammer means disposed within the first hous-
ing and rotatable about its axis; a chute connected to the first
housing at a position closer to the axis than the first conduit
means, and discharge means connected to the second housing at a
position closer to the axis than the second conduit means; the
first conduit means permitting a whirling gas stream produced in
the first housing by the rotation of the hammer means to flow into
the second housing and circulate about its axis therein, the $
second conduit means permitting a portion of the circulating gas
to flow into the first housing, the discharge means serving to let
20 the remainder of the circulating gas out of the second housing,
whereby a material fed to the interior of the first housing is
crushed by the hammer means and is then sent by the gas through
the first conduit means into the second housing to circulate about t
its axis therein, the circulating material is classified into
coarse fragments and fine fragments by the cooperative action of
centrifugal force and conveying force of the gas stream, the fine
fragments are sent to the discharge means by the gas stream and the
coarse fragments are sent through the second conduit means into the
first housing by the gas stream.
The crushing apparatus having a classifier of this in- .;
vention thus comprises a first housing and a second housing sub- F
stantially coaxial with each other; first conduit means and second
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conduit means for communicating the first housing and the second
housing, the first conduit means being connected to both the
housings at a position proximate to the peripheral walls thereof
and having an inner space having an annular cross section, the
second conduit means being connected to both the housings at a
position closer to the axis of the housings than the first conduit
means; hammer means disposed within -the first housing and rotatable _
about its axis; a chute connected to the first housing at a posi-
tion closer to the axis than the first conduit MeanS; and dis-
charge means connected to the second housing at a position closerto the axis than the second conduit means.
The rotation of the hammer means produces in the first
housing a whirling gas stream, which flows through the first con- L
duit means into the second housing and circulates about its axis
therein. A portion of the circulating gas flows through the
second conduit means into the first housing, whilst the remainder
of the gas flows out of the second housing through the discharge
means.
F~
842 1,
The material fed into the first housing is crushed
by the hammer means and is then sent by the gas stream through
the first conduit means into the second housing, in which it
circulates about its axis and is classified into coarse fragments
and fine fragments by the cooperative action of the centrifugal
force and the conveying force of the gas stream. The fine
fragments are sent to the discharge means by the gas stream,
whereas the coarse fragments are sent by the gas stream back
into the first housing through the second conduit means. In
other words, the material is crushed into fragments within the
first housing and such fragments of all sizes are promptly sent
to the second housing through ~he first conduit means. The
fragments are then made to circulate together with the gas
stream in the second housing and are effectively classified into
coarse fragments and fine fragments by the cooperative action
of the centrifugal force and the conveying force of the gas
stream.
Since the gas stream generated by the rotation of the
hammer means is used to obtain a whirling flow for classifying
the crushed fragments, the economy of overall power is made
possible by efficiently using the energy from the hammer means.
After classified, the fine fragments are promptly
let out of the apparatus on the gas stream through the discharge
means, whereas the coarse fragments are returned through the
second conduit
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means to the first housing by the gas stream. In this instance
as well, an effective use is made of the differentiation of
pressure within the first housing caused by the rotation of the
hammer means. To state this in more detail, since the second
conduit means is disposed closer to the axis of both the housings
than the first conduit means, the pressure in the vicinity of
the opening of the second conduit means to the first housing
is higher than that in the vicinity of the opening thereof to
the second housing.
Accordingly, after classified, the coarse fragments
circulating near the opening of the second conduit means to the
second housing are positively and smoothly returned to the first
housing owing to the inhaling force caused by the a~oresaid
pressure differentiation.
In this way the inhaling force caused by the pressure
differentiation which is brought about by the rotation of the
hammer means is used for the feed-back of the coarse fragments
to the first housing, whereby a further economy of power is
made possible.
As stated above, the apparatus according to the
present invention uses the inhaling force caused by the pressure
differentiation owing to the rotation of the hammer means which
is the essential factor of a crushing apparatus.
Therefore, not only its construction is simple but
it is positively capable of both crushing and
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4;~
classifying with a small power supply, and its running cost will
be low.
In addition, the coarse fragments introduced through
the first conduit means into the second housing travel to the
inlet of the second conduit means in circulating motion wlthin the
second housing owing to the gas strearn and the centrifugal force,
instead of proceeding directly thereto.
In the course of this travel, the fragments are cooled
by being exposed to the gas stream. This amounts to a secondary
advantage, namely the prevention of over-heating in crushing heat-
sensitive material.
-
The present invention thus provides an economicalapparatus with a simple construction and classifying its fragments
by a small power supply.
The present invention also provides an apparatus which
is designed to discharge the fragments o~ substantially uniform
size irrespective of the kind of the material.
The present invention also provides an apparatus which
is capable of controlling, as desired, the size of the crushed
fragments of the material to be discharged from the apparatus.
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1~D3~42
The present invention will be further lllustrated by
way of the accompanylng drawings in which
Fig. 1 is a side elevation in vertical section showing
an embodiment of this invention;
Fig. 2 is a view in section taken along the line II-II
in Fig. l;
Fi~. 3 is a view in section taken along the line III-III
in Fig. l;
Figs. 4 and 5 are fragmentary side elevations in verti-
cal section showing the prlncipal part of another embodiment;
Fig. 6 is a view in section taken along the line VI-VI
in Fig. 5; and
Fig. 7 is a fragmentary side elevation in vertical sec-
tion showing the principal part of still another embodiment.
The drawings show a first housing 1 constituting a
crushing apparatus and a second housing 2 constituting a centri-
fugal classifier. The first housing 1 and second housing 2, both
cylindrical, have substantially 'che same diameter and are coaxially
arranged adjacent to each other.
Disposed within the first housing 1 in aliynment with
its axis 3 is a rotary shaft 4 driven by a motor ~not shown) and
having hammer means 5 fixed thereto. The hammer means 5 comprises
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a disc 6 keyed to the rotary shaft 4 coaxially therewith and a
plurality of crushing blades 7 secured to the periphery of the
disc 6 with substantially e~ual spacing therebetween. The first
housing 1 is formed, over its entire inner periphery, with a
serrated impact crushing surface 8 which is opposed to the track
of revolution of the crushing blades 7. The crushing blades 7
and impact crushing surface 8 combine to crush the material fed
to the interior of the first housing 1.
A side partition plate 9 disposed between the first
housing 1 and the second housing 2 is in the form of a disc and
is coaxial with the rotary shaft 4. Between the outer periphery
of the partition plate 9 and the inner peripheral surfaces of
the first housing 1 and second housing 2, an annular space is
Eormed which serves as first conduit means 10. The side partition
plate 9 has circular arc apertures which are arranged circum-
ferentially about the axis 3 and spaced apart from each other.
The apertures serve as second conduit means 13. The partition
plate 9 is secured to a side wall 12 of the second housing 2 by
bolts and nuts 11.
Alternatively, the second conduit means 13 may be in
the form of a continuous annular aperture centered abou-t the
axis 3. In this case, the inner portion of partition plate 9
is secured to the side wall 12 of the second housing 2 by bolts
and nuts.
The flrst conduit means 10 is therefore positioned in
proximity to the inner peripheral surfaces of the first housing
1 and the second housing 2, whilst the second conduit means 13
is positioned closer to the axis 3 than the first conduit means
10. The interior of first housing 1 communicates with the
interior of second housing 2 through both the conduit means 10
and 13. The second conduit means 13 is sufficiently large -to
permit passage of coarse crushed fragments.
3~2
Side wall 14 of the first housing 1 opposite to the
side partition plate 9 is provided with a chute 15 for feeding
material into the first housing 1. The chute 15 communicates
with the first housing 1 through an opening 16 in the side wall
14. The opening 16 is positioned closer to the axis 3 than the
first conduit means 10.
A plurality of guide vanes 17 for guiding the gas which
comes from the first housing 1 into the second housing 2 in the
form of a whirling stream are provided in the interior of the
second housing 2 at substantially equal spacing along the first
conduit means 10 in proximity to its opening.
The number thereof is determined so as to allow the
~as stream introduced through the first conduit means 10 to
enter at a uniform angle over the entire circumference.
The guide vanes 17 are attached to the side wall 12 of
the second housing 2 by pins provided adjacent to the first
conduit means 10, each of the vanes 17 being fixed or pivotable
as desired about an axis approximately in parallel to the axis 3.
The inner surface of side wall 12 of the second housing
2 is in the form of a slanting wall surface 1~ which slants
toward the axis 3, and the side wall 12 has an opening coaxial
with the axis 3. Discharge means 19 is Eixed to the open portion
of the side wall 12. The interior space of the second housing
2 is therefore constricted toward the axis 3. The opening of
the first conduit means 10 to the second housing 2 is positioned
further into the second housing 2 than the opening of the second
conduit means 13 to the second housing 2 so as to be disaligned
with the latter stepwise in the direction parallel to the axis 3.
The apparatus of the foregoing construction operates
in the following manner. The material fed to the first housing
1 from the chute 15 is first crushed by the impact force of
crushing blades 7 of the hammer means 5 and further crushed into
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smaller pieces by heing forced against the impact crushing
surface 8. At this time, the high-speed rotation of the hammer
means 5 produces in the first housing 1 a whirling gas stream,
which is guided through the first conduit means 10 into the
second housing 2 by the guide vanes 17. The gas introduced
into the second housing 2 and turning in eddy current then
partially flows through the second conduit means 13 into the
first housing 1 owing to the pressure gap between the first
housing 1 and the second housing 2 which is produced by the
rotation of the hammer means 5, whilst the remainder of the gas
flows out of the second housing 2 via the discharge means 19.
Accordingly, the material crushed in the first housing
1, whether coarse or fine, is discharged from the first housing
1 into the second housing 2 through the first conduit means 10
as carried on the whirling gas stream produced by the rotation
of the crushing blades 7. The crushed fragments sent into the
second housing 2 are made to circulate about the axis 3 on the
gas stream therein and are classified into coarse fragments and
fine fragments by the cooperative action of centrifugal force
and the conveying force of the gas stream acting toward the
axis 3.
More specifically, both the fine fragments and the
coarse fragments have the tendency oE flowing toward the dis-
charge means 19 while being circulated by the gas stream. The
centrifugal force acting on the crushed material owing to the
circulatory motion is such that the coarser the fragments, the
greater the force, whereas the finer the fragments, the smaller
the force. With fine fragments, therefore, the force to convey
the fragments toward the discharge means 19 overcomes the
centrifugal force, with the result that the fine fragments are
let out of the apparatus through the discharge means 19. With
coarse fragments, on the other hand, the conveying force toward
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the discharge means 19 comes into balance with the centrifuga]
force, permitting the coarse fragments to continuously circulate
in the vicinity of the inlet of the second conduit means 13.
Consequently, the coarse fragments are ret~lrned to the interior
of the first housing 1 through the second conduit means 13 by
being withdrawn owing to the pressure gap between the two housings
1, 2 produced by the rotation of the hammer means 5 within the
first housing 1. In this case, since the construction is such
that the openings of the two conduit means 10, 13 to the second
housing 2 are disaligned stepwise and the inner surface of the
side wall 12 of the second housing 2 is formed into the slanting
wall surface 18 as described hereinbefore the coarse ragments
will reach the opening of the second conduit means 13 by the
combination of the conveying force of said slanting wall surface
18 acting toward the partition plate 9 and the centriugal orce,
without relying on the inhaling force caused by the pressure gap
between the two housings 1, 2, and then return to the interior
of the first housin~ 1 smoothly.
The coarse fragments sent from the first conduit means
10 into the second housing 2 get cooled by the whirling gas
stream while progressively proceeding toward the second conduit
means 13 in circulation. This is particularly advantageous
when processing a heat-sensitive material.
The coarse fragments are then crushed again by the
hammer means 5 into smaller fragments, which are sent into the
second housing 2 by way of the first conduit means 10. In this
way the crushing operation is carried out effectively, permitting
fine fragments alone to be drawn out o the discharge means 19.
The angle of the guide vanes 17 is variable to adjust
the magnitude of speed component for sending the crushed material
in the second housing 2 toward the axis 3. This makes :it
possible to control the particle size of the material to be
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withdrawn from the discharge means 19.
Fig. 4 shows another embodiment in which, as seen in
vertical section along a plane passing through the axis 3, the
inner surface of outer portion of second conduit means 13
defining the interior space thereof is in the form o~ a slanting
surface 21 which flares toward the first housing 1 with respect
to the axis 3. The slanting surface 21 serves to smoothly
return the circulating coarse fragments in the second housing 2
to the first housing 1.
Furthermore, the slanting surface 21 of the second
conduit means 13 protrudes largely into the first housing 1 and
thereby protruding the outer edge portion of the opening of the
second conduit means 13 to the first housing 1, whereb~ the
coarse fragments returned through the second conduit means 13
can be brought to the suitable crushing position more accurately
to ensure effective crushing operation.
Figs. 5 ad 6 show another embodiment in which the side
partition plate 9 of annular shape is provided with a barrier
plate 20 adjacent thereto rotatable in a circumferential direction
by a handle 22. When rotated, the barrier plate 20 changes the
size of the opening of the second conduit means 13 and thereby
controls the amount of the coarse fragments to be returned from
the second housing 2 to the first housing 1.
If for example a large quantity of coarse fragments
are sent from the first housing 1 into the second housing
without being finely divided, the barrier plate 20 is adjusted
to enlarge the opening of the second conduit means 13. This
increases the quantity of the fragments sent back into the first
housing 1, in which the material is further crushed to smaller
sizes and then discharged into the second housing 2.
Fig. 7 shows another embodiment which is adapted to
control the quantity of the fragments to be returned to the
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first housing 1 as in Figs. 5 and 6. A barrier plate 20 operable
from outside the apparatus by a handle 22 is fixedly provided
~ over the inner peripheral surface of the annular second conduit
i means 13 and is movable in the direction of axis 3. The interior
space of the second conduit means 13 enlarges toward the first
housing 1. The barrier plate 20, when moved, controls the size
j of the opening of the interior space of the second conduit means
13.
Indicated at 23 is a guide which is secured to the
side wall 12 by bolts and nuts or the like.
Though in the embodiment described herein the side
partition plate 9 serves dually as one of the side walls of the
irst housing 1 and that of the second housing 2, it is possible
¦ to arrange the two housing 1, 2 at a suitable distance from each
~ other by providing each of the housings with a side wall plate.
1 The single side partition plate 9 serving dually as in said
embodiment, of course, helps simplify the construction. In
addition, other merits as below may be expected.
~ When crushing materials which have brittleness at low
l 20 temperature such as rubber, plastics, etc., they are usually
refrigerated by means of refrigerant prior to feeding into the
crushing apparatus. In the case of processing such refrigerated
material in a crushing apparatus and a classifying apparatus
with some distance therebetween the coarse fragments of the
crushed material to be returned to the crushing apparatus are
liable to warm up during their return trip, making it difficult
to crush at the second round. In order to remove this setback
an extra apparatus for cooling the coarse fragments is required,
which is a disadvantage in respect of equipment and economy.
The coarse fragments are effectively prevented from warming up
by partitioning the two adjacent housings 1, 2 with the single
partition plate 9 as described hereinbefore. Furthermore, said
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coarse fragments are exposed to the gas stream within the second
housing 2 and are expected to remain cool. Thus a low con-
sumption of the refrigerant for precooling the material is
assured, and the addition of a cooling means is not required,
which amount to an advantage in respect of economy and equipment.
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