Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THh INVENTION
Field of the Invention
The present invention relates to disk refiners, and more
particularly to disk refiners for providing a low intensity
treatment of pulp fiber to increase the strength
characteristics of the pulp and reduce the amount of specific
energy required during refining.
Description of the Prior Art
It has recently been shown that low intensity treatment
of certain pulp fiber increases the strength of characteris-
tics of the pulp while reducing the amount of specific energy
required. In this context, intensity for a given throughput
is proportional to the horsepower per inch of refiner bar
crossings, as disclosed in U.S. Patent No. 4,661,911 and
corresponding Canadian Letters Patent No. 1,249,646, in which
specific operational parameters of a refining system are
sensed to control the refiner disk spacing by way of a
gearmotor. A reduction in intensity, therefore, may be
accomplished by increasing the number of refining surfaces
in a given refiner.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide a
new and improved multi-disk refiner for low intensity treat-
ment of pulp fiber.
The above object is achieved, according to the present
invention, in providing an increase in the number of refining
surfaces by mounting several rigid refiner disk in a manner
so as to provide each disk with complete freedom of axial
movement. The rotating refiner disks can be mounted so
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as to be axially slidable on a torque transmitting section
of a shaft so that rotational forces can be transmitted to
the disks while an axial motion thereof is not restrained.
The torque transmitting section of the shaft may be splined
or have a geometrical cross-sectional (e.g. square,triangular
or other polygon) and the rotatable disks may have corre-
spondingly shaped central openings receiving the respective
torque transmitting section. Non-rotatable or fixed refiner
disks can be supported by several support lemens (e.g. pins,
guide rails and the like) which prevent rotation of the disk,
but permit each such refiner disk to slide in the axial
direction. The shaft and the stator support elements can be
constructed of a hard material, and the sliding members may
be constructed of softer, wearable material. The sliding
members may also be molded from a structural plastic material.
The non-rotating disks each include a central aperture for
receiving the shaft therethrough and for supporting the flow
of paper stock and the rotating disks each include ports to
permit the paper stock to flow therethrough and be properly
distributed to each pair of refiner disks.
The refiner may be loaded to the desired power by
axially adjusting the last stationary element of a series of
refiner disks.
Inasmuch a~ the refiner di~ks are not axially
secured to the refiner shaft or housing, the number of plates
may easily be increased or decreased in the refiner to match
the process requirements.
Also, inasmuch as there is no limitation on the
axial movement of the refiner disks, a large number of plates
may be added to a refiner to increase the overall capacity of a
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given size of the refiner. Therefore, a smaller diameter
refiner having many refiner discs may be used in place of a
large refiner having fewer discs. This reduces the capital
expense for large horsepower, low speed motors which are
required by the larger diameter refiners.
BRIEF DESCRIPTION OF THE DRAWINGS_
Other objects, features and advantages of the
invention, its organization, construction and operation will
be best understood from the following detailed description,
taken in conjunction with the accompanying drawings, on which:
FIG. 1 is a fragmentary sectional view of a
refiner constructed in accordance with the present invention;
FIG. 2 is a fragmentary enlarged view of a portion
of the refiner illustrated in FIG. l;
FIG. 3 is a partial sectional view taken
substantially along the parting line III-III of FIG. l;
FIG. 4 is a fragmentary sectional view
illustrating a shaft having a square torque transmitting
section;
FIG. 5 is a fragmentary sectional view illus-
trating a shaft having a triangular torque transmitting
section;
FIG. 6 is a fragmentary sectional view illus-
trating a shaft having a hexagonal torque transmitting section;
FIG. 7 is a fragmentary sectional view illus-
trating an arcuate guide rail support structure;
FIG. 8 is a fragmentary sectional view illus-
trating a txapezoidal guide rail support structure; and
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FIG. 9 is a fragmentary sectional view illus-
trating an oval support element structure.
DESCRIPTICN OF THE PREFERRED EMBODIMENTS
Referring to the drawings, a refiner,constructed
in accordance with the present invention, is generally
illustrated at 10 as comprising a first housing part 12 having
a recess therein which, with a second housing part 14 defines
a refining chamber 16. The refiner comprising a paper stock
flow path including a paper stock input 18 to the refining
chamber 16 and a paper stock output 20 from the refining
chamber 16.
The housing part 12 comprises a bore 22 with a
bearing 24 therein supporting a shaft 26 for rotation. The
haft 26 includes a splined section 28 for mounting a
plurality of rotatable refiner discs 30 each of which has a
central aperture 32 complemental to the spline 28.
As seen in each of the figures, each rotatable
disc 30 comprises a plurality of ports 34 for supporting a
flow of stock.
Alternately mounted with the rotatable disc 30 is
a plurality of refiner discs 36 each of which is provided with
a central aperture 38 for receiving the shaft therethrough and
for supporting a flow of paper stock. Each of the plates 36
further comprises a plurality of bores 42 for receiving a
respective pin 44 mounted to the housing part 12.
Each of the rotatable refiner discs 30 is axially
slidable along the spline section 28 of the shaft 26. By the
same token, each of the non-rotatable refiner discs is axially
slidable on the pins 44.
Each of the refiner discs 30 and 36 and each of a
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pair of end discs 46 and 48 respectively mounted to the
housing parts 12 and 14, comprise refiner bars which accomplish
the actual refining operation.
As previously mentioned, the refiner may be
loaded with the desired power by axially adjusting the last
stationary element, in this case the element 46 or the
element 48. This may be accomplished by screw techniques, or
by a gear motor or the like and essentially adjust the
relative spacing of the housing parts 12 and 14, as indicated
by the double-headed arrow 50.
As shown in FIG. 1, the splined shaft may be
provided with an end cap 52 secured to the distal end of the
shaft by way of at least one screw 54 which may be employed to
maintain the rotatable refiner disc on the shaft prior to
assembly of the left and right-hand sides of the housing
parts illustrated in FIG. 1. After assembly, of course, the
axial movement of the refiner disc are limited by the fixed
refiner disc 46 and 48.
As mentioned above, and stated in slightly
different terms, is to essentially match a given size refiner
to process the requirements by providing the refiner with a
number of refining discs which will accomplish a low intensity
treatment so as to increase the strength characteristics of
the pulp and reduce the amount of speci.fic energy required for
the refining process.
This may be readily accomplished in practicing
the present invention with structure of the type illustrated
in FIG. 1 in which the housing parts 12 and 14 are separated
from one another and the desired number of refiner discs 30
and 36 are mounted, respectively, on the splined shaft 26,28
and on the support pins 44.
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As mentioned above, the torque transmitting
section of the shaft may comprise various cross-sectional
shapes. Examples of these are illustrated in FIGS. 4-6.
Referring to FIG. 4, a refiner disk 36A includes
a square central aperture 32A for receiving a square torque
transmitting section 26A of the shaft.
In FIG. 5, a disk 36B includes a central aperture
32B in the form of a triangle for receiving a triangular
section 26B of a shaft.
In FIG. 6, the disk 36C includes a hexagonal
central opening 32C for receiving a hexagonal section 26C of a
5haft.
The above torque transmitting constructions, of
course, are not the only constructions which may be employed in
practicing the invention.
By the same token, the support pins 44 of FIGS. 1-
3 may be replaced by other structures. Examples of such
structures are illustrated in FIGS. 7-9.
Referring to FIG. 7, a disk 36D includes a
projection having an arcuate groove 42D for slidingly receiving
a complemental arcuate projection 44D which is secured to the
refiner housing.
In a similar, but somewhat reverse manner, FIG. 8
illustrates a disk 36E carrying a trapezoidal projection 42Eto
be slidingly received in a complemental groove 4 4E extending
from the wall of the refiner housing.
In somewhat the same manner as in FIGS. 1-3, FIG.
9 illustrates the use of an oval support pin 44F to be
slidingly received in an oval aperture 42F provided on an
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extension of the refiner disk 36F.
Although we have described our invention by
reference to particular illustrative embodiments thereof, many
other changes and modifications of the invention may become
apparent to those skilled in the art without departing from the
spirit and scope of the invention. We therefore intend to
include within the patent warranted hereon all such changes and
modifications as may reasonably and properly be included within
the scope of our contribution to the art.
