Note: Descriptions are shown in the official language in which they were submitted.
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1324908
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PAPER-MAKING MATERIAL DEPOSITION APPARATUS
This invention relates to a paper-making material
deposition apparatus of the tower type, in which a paper-
making material with a concentration of 10 to 30% is
charged into a tower from an inlet at the top to be
deposited and diluted and progressively taken out of the
tower from the bottom thereof.
The prior art paper-making material deposition
apparatus of the type referred to above is used as a
virgin pulp stock tower or an ink removal tower for
causing swelling of paper-making material consisting of
used paper in the presence of an ink-removing agent while
liberating or making easier the liberation of ink adhering
to the material. The apparatus comprises a tower having a
paper-making material inlet provided at the top for
depositing the paper-making material in the inside and a
stirrer rotatable in a horizontal plane in and adjacent to
the bottom of the tower and having diluting-water jet
nozzles and diluting-water supply passages leading to the
jet nozzles (as disclosed in, for instance, Japanese
Patent Publications SHO 55-37638 and SHO 57-55835).
In this prior art apparatus, a driver including a
motor and a speed reduction unit is disposed on the tower
top for rotating the stirrer, and the driver transmits
drive force to the upper end of a vertical shaft/ to the
l~wer end of which the center of the stirrer is secured,
and which is supported at the center of the tower bottom
and the center of the tower top.
The stirrer is rotated in a deposited paper-
making ~aterial layer on the tower bottom while jetting
diluting water from the jet nozzles.
Some such towers are of a gigantic size having a
diameter o 10 m and a height of 20 m. The top of the
vertical shaft is jo~rnaled at the center of the tower
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top, and the driver is disposed near the center. Therefore,
the paper-making material inlet has to be provided at an
eccentric position with respect to the tower top center.
therefore, the top surface of the paper-making material
deposited in the tower is not uniform in level but s higher
in level in the neighbourhood of a position directly
underneath the paper-making material inlet. For this reason,
the load exerted on or resistance offered to the stirring
wings of the stirrer rotated horizontally adjacent to the
tower bottom by the vertical shaft which is as long as 20m
varies greatly. This means that the vertical shaft support
unit and stirrer have to have considerably high mechanical
strength.
An object of the invention is to provide a paper-
making material deposition apparatus in which a substantiallyuniform load is applied to the stirring wings of the stirrer.
To attain the above obiect of the invention, there
is provided a paper-making material deposition apparatus in
which a stirrer rotatable in a horizontal plane in and
adjacent to the bottom of a tower has an integral shaft
depending from it and penetrating the center of the tower
bottom, and a driver for rotating the shaft is disposed
beneath the center of the tower bottom.
Thus according to an aspect of the present invention
there i8 provided a paper-making material deposition apparatus
comprising: a foundation having a space therein; a tower built
on said foundation and having a top surface provided at its
centre with an inlet for a paper-making material and a bottom
surface for depositing a paper-making material which is
charged from said inlet; a shaft having one end projecting
upwardly from said bottom surface of said tower substantially
at the centre thereof and the other end projecting downwardly
into said space of said foundation, said shaft having a
diluting-water supply passage and a paper-making material
tak~out passage formed therein; a stirrer fixed to an upper
end of a portion of said shaft projecting upwardly from said
,. ...
13249~8
2a
bottom surface of said tower and provided with a pair of
stirring wings which are rotatable in a substantially
horizontal plane in and adjacent to said bottom surface of
said tower, each of said stirring wings being provided with
respective diluting-water jet nozzles and diluting-water
supply passages communicating with said diluting-water supply
passage of said shaft, and paper-making material suction ports
and paper-making material takeout passages communicating with
said paper-making material takeout passage of said shaft;
lo bearing means disposed in said space of said foundation for
rotatably supporting a portion of said shaft projecting
downwardly into said space of said foundation; and drive means
disposed in said space of said foundation and provided with
speed reduction means for rotating said shaft via said bearing
means.
The driver disposed beneath the tower bottom center
transmits drive force to the shaft integrally and downwardly
extending from the stirrer and penetrating the tower bottom
center. Thus, the conventional vertical stirrer support shaft
aan be dispensed with, and the paper-making material inlet can
be provided near the tower top center. Thus, the paper-making
material charged into the tower can be uniformly distributed
from the center, and there is no need of particularly
reinforcing the mechanical strength of the stirring wings of
the stirrer.
B
1324908
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The above and other objects and features of the
invention will become more apparent from the following
detailed description with reference to the accompanying
drawings.
Figure 1 is a side sectional view showing an
embodiment of the paper-making material deposition
apparatus according to the invention;
Figure 2 is a sectional view taken along line II-
II in Figure l;
~ igure 3 is a fragmentary enlarged-scale
sectional view showing the apparatus of Figure l; and
Figure 4 is a view similar to Figure 1 but
showing a different embodiment of the paper-making
material deposition apparatus according to the invention.
Figures 1 to 3 show a first embodiment of the
paper-making material deposition apparatus according to
the invention. Referring to the Figures, reference
numeral 1 designates a tower, 2 a paper-making material
inlet provided at the center of the tower top, and 3 a
stirrer rotatable in a horizontal plane in the tower
adjacent to the bottom thereof.
The stirrer 3 includes a hollow central stem 4
and a plurality, i.e., two in this embodiment, of hollow
horizontal stirring wings 5 circumferentially uniformly
spaced apart around and extending outwardly from the stem
4. Each stirring wing 5 has a plurality of diluting-water
jet nozzles 6 provided at a predetermined interval along
its front surface in the direction of its rotation as
shown by the solid arrow in Figure 2. A hollow short
shaft 7 depends integrally and concentrically from the
lower surface of the stem 4.
Below the center of the bottom 1' of the tower 1,
a space 8' is formed in a concrete foundation 8. A frame
9 is built on the bottom of the space 8' such that it
surrounds a lower half of the shaft 7. An inner race lOa
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of a bearing 10 is secured to the top of the frame 9 such
that it is concentric with the shaft 7. The shaft 7 is
provided with a flange 11 extending from its outer
periphery. An outer race lOb of the bearing 10 is secured
to the lower surface of the flange 11. The outer
periphery of the outer race lOb is provided with a gear
lOc, which is in mesh with a gear 12' provided on an
output shaft of a driver 12 disposed on the frame 9 and
consisting of a motor, a speed reduction gear train, etc.
The bearing 10 serves to receive the drive force from the
driver 12 and enables smooth rotation of the flange 11,
and hence the stirrer 3 integral with the shaft 7. In
addition, it receives the thrust of the stirrer 3.
In this first embodiment, the inside of each
stirring wing 5 of the stirrer 3 has a dual structure. An
inside pipe 5' of the stirring wing 5 serves as a paper-
making material take-out passage 14 which has a paper-
making material suction port 14' open at the end of the
stirring wing 5. A space defind between the inner surface
of the stirring wing 5 and the outer surface of the inside
pipe 5' serves as a diluting-water supply passage 13.
Instead of this dual structure, the inside of each
stirring wing 5 may be divided by a partition member (not
shown) into a diluting-water supply passage 13 extending
along the front surface and a paper-making material take-
out passage 14 extending along the rear surface.
A cylinder 15 spaced apart a distance from and
surrounding an upper half of the shaft 7 depends from the
lower surface of the central stem 4 of the stirrer 3, and
its lower end sealedly and rotatably downwardly extends
into an upper joint box 16 rotatably and sealedly mounted
on the outer periphery of the shaft 7. A diluting-water
supply ductline 17 is connected to the upper joint box 16,
and the upper end of a cylindrical space defined inside
the cylinder 15 is communicated through a communication
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hole 4' formed in a lower portion of the wall of the stem
4 with the diluting-water supply passage 13 in each
stirring wing 5. When the stirrer 3 is rotated in unison
with the shaft 7 and cylinder 15 at a rate of 15 to 20 rpm
from the driver 12 while supplying diluting water to the
upper joint box 16, the diluting water is caused to rise
through the cylindrical space surrounded by the cylinder
15 to enter the inner space of the stem 4 through each
communication hole 4' and flow to each passage 13 so as to
be jetted from the jet nozzles 6.
In order to be able to extract the diluted paper-
making material at the tower bottom to the outside of the
tower 1 during the rotation of the stirrer 3, the upper
end of the shaft 7 and paper-making material take-out
passage 14 in each stirring wing 5 are communicated with
each other by a joint cylinder 18. The lower end of the
shaft 7 sealedly and rotatably downwardly extends into a
lower joint box 19 secured to the bottom of the space 8'
in the concrete foundation 8~ and a paper-making material
extraction ductline 20 communicated with a suction pump
~not shown) is connected to the lower joint box 19.
With the first embodiment having the above
construction, as in the prior art structure disclosed in
the Japanese Patent Publication SHO 57-55835 mentioned
earlier, it is possible to cause rotation of the stirrer 3
in a horizontal plane adjacent to the tower bottom to
cause diluting water to be jetted from the jet nozzles 6
on the front surface of the stirring wings in the
direction of rotation so as to dilute the paper-making
material on the tower bottom to a concentration of about
4% if the concentration before the dilution is about 10%
and enable the diluted paper-making material to be
extracted through the paper-making material suction port
14', paper-making material take-out passages 14 in the
stirring wings 5 and shaft 7. In this embodiment, the
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paper-making material take-out passage 14 is provided in
each of the two stirring wings 5, but it is possible to
provide a take-out passage in only a single stirring wing.
Figure 4 shows a second embodiment of the
invention. In this instance, like the prior art structure
shown in the Japanese Patent Publication SHO 55-37638, the
side surface of the tower l adjacent to the bottom thereof
is provided with a paper-making material extraction port
in which a suction pump 21 is mounted. Paper-making
material having been diluted by the stirrer 3 is extracted
through this extraction port. The entire inner space of
each stirring wing 5 of the stirrer 3 constitutes a
diluting-water supply passage, and the diluting-water
supply ductline 17 is connected to a lower joint box l9.
The cylinder 15 and upper joint box 16 in the previous
embodiment are unnecessary in this case.
As has been described in the foregoing, the
structure according to the invention is free from any
vertical stirrer support shaft journaled at the tower top
center or any driver for rotating such a vertical shaft,
so that it is possible to provide the paper-making
material inlet near the tower top center. The paper-
making material charged into the tower from the inlet thus
is substantially uniformly distributed in the tower, thus
precluding variations of the load on the stirring wings of
the stirrer rotated horizontally in the tower adjacent to
the bottom thereof. Further, the downwardly extending
shaft for rotating the stirrer may be far shorter than
that of the conventional vertical shaft having a height of
10 to 20 m. Owing to this fact and also owing to the
substantial freedom from variations of the load on the
stirring wings of the horizontally rotated stirrer, the
shaft need have only low mechanical strength.
