U.S. patent application number 14/380258 was filed with the patent office on 2015-02-05 for manufacturing method and manufacturing device for bundle product.
This patent application is currently assigned to TORAY INDUSTRIES, INC.. The applicant listed for this patent is TORAY INDUSTRIES, INC.. Invention is credited to Osamu Kuramata, Nao Minaki, Daikichi Nishioka, Makoto Uchino.
Application Number | 20150034755 14/380258 |
Document ID | / |
Family ID | 49082208 |
Filed Date | 2015-02-05 |
United States Patent
Application |
20150034755 |
Kind Code |
A1 |
Kuramata; Osamu ; et
al. |
February 5, 2015 |
MANUFACTURING METHOD AND MANUFACTURING DEVICE FOR BUNDLE
PRODUCT
Abstract
Provided is a manufacturing method for a bundle product that
includes an inspecting step of inspecting two or more threads
continuously running in parallel in the longitudinal direction, a
collecting step of collecting the threads, and a cutting step of
cutting, after completion of the collecting, all the collected
threads at a predetermined position, to obtain a bundle product
having plural threads converged into a bundle. In the manufacturing
method, an amount of collection in the collecting step is adjusted
on the basis of inspection results obtained in the inspecting step
so that at least one managed quantity for plural threads selected
from a group including a total number, a total weight, a
representative weight, a total outside diameter value, a
representative outside diameter value, a total surface area, and a
representative surface area of the plural threads constituting the
bundle product exceeds a predetermined value.
Inventors: |
Kuramata; Osamu; (Otsu-shi,
JP) ; Uchino; Makoto; (Otsu-shi, JP) ;
Nishioka; Daikichi; (Iyo-gun, JP) ; Minaki; Nao;
(Iyo-gun, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TORAY INDUSTRIES, INC. |
TOKYO |
|
JP |
|
|
Assignee: |
TORAY INDUSTRIES, INC.
TOKYO
JP
|
Family ID: |
49082208 |
Appl. No.: |
14/380258 |
Filed: |
January 29, 2013 |
PCT Filed: |
January 29, 2013 |
PCT NO: |
PCT/JP2013/051850 |
371 Date: |
August 21, 2014 |
Current U.S.
Class: |
242/472.8 |
Current CPC
Class: |
B65H 54/58 20130101;
B01D 63/021 20130101; B01D 2323/42 20130101; G01N 21/952 20130101;
B65H 63/065 20130101; B01D 65/102 20130101; B65H 51/015
20130101 |
Class at
Publication: |
242/472.8 |
International
Class: |
B65H 54/58 20060101
B65H054/58; B65H 63/06 20060101 B65H063/06 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 29, 2012 |
JP |
2012-043208 |
Claims
1. A manufacturing method for a bundle product, comprising the
steps of: inspecting two or more threads continuously running in
parallel in a longitudinal direction; collecting the threads; and
cutting, after completion of the collecting, all the collected
threads at a predetermined position, to obtain a bundle product
having a plurality of threads converged into a bundle, wherein an
amount of collection in the collecting step is adjusted on the
basis of inspection results obtained in the inspecting step so that
at least one managed quantity for a plurality of threads selected
from a group including a total number, a total weight, a
representative weight, a total outside diameter value, a
representative outside diameter value, a total surface area, and a
representative surface area of the plurality of threads
constituting the bundle product exceeds a predetermined value.
2. The manufacturing method for a bundle product according to claim
1, wherein the collecting step is a winding and collecting step of
collecting the threads during rotation.
3. The manufacturing method according to claim 1, wherein the
collecting step is a cutting and collecting step of collecting the
threads while cutting the threads to a certain length.
4. The manufacturing method according to claim 1, wherein the
collecting step is a turn-around collecting step of collecting the
threads while turning around the threads at a certain length.
5. The manufacturing method for a bundle product according to claim
1, wherein the threads are hollow fiber membranes.
6. The manufacturing method for a bundle product according to claim
1, wherein the managed quantity for the plurality of threads is the
total surface area of the plurality of threads constituting the
bundle product.
7. The manufacturing method for a bundle product according to claim
1, wherein the managed quantity for the plurality of threads is the
representative surface area of the plurality of threads
constituting the bundle product.
8. The manufacturing method for a bundle product according to claim
6, wherein in the inspecting step, outside diameters of the threads
are measured, and surface areas of the threads are calculated on
the basis of the obtained measured values of the outside
diameters.
9. The manufacturing method for a bundle product according to claim
1, further comprising the steps of: removing a thread determined to
contain a defect in the inspecting step from the bundle of the
plurality of threads, wherein an amount of collection in the
collecting step is adjusted so that at least one managed quantity
for a plurality of threads selected from a group including a total
number, a total weight, a representative weight, a total outside
diameter value, a representative outside diameter value, a total
surface area, and a representative surface area of the plurality of
threads constituting a bundle product after the thread containing
the defect is removed in the removing step exceeds a predetermined
value.
10. A manufacturing device for a bundle product including an
inspecting unit that inspects two or more threads continuously
running in parallel in a longitudinal direction, a collecting unit
that collects the threads, and a cutting unit that, after
completion of collecting, cuts all the collected threads at a
predetermined position, to obtain a bundle product having a
plurality of threads converged into a bundle, wherein the
manufacturing device further includes: a collection-amount
adjusting unit that can adjust an amount of collection by the
collecting unit on the basis of inspection results obtained by the
inspecting unit so that at least one managed quantity for a
plurality of threads selected from a group including a total
number, a total weight, a representative weight, a total outside
diameter value, a representative outside diameter value, a total
surface area, and a representative surface area of the plurality of
threads constituting the bundle product exceeds a predetermined
value.
11. The manufacturing device for a bundle product according to
claim 10, wherein the threads are hollow fiber membranes.
12. The manufacturing device for a bundle product according to
claim 10, wherein the inspecting unit includes means for
calculating surface areas of the threads on the basis of measured
values of outside diameters obtained by the inspecting unit that
measures the outside diameters of the threads.
13. The manufacturing device for a bundle product according to
claim 10, wherein on the assumption that a thread determined to
contain a defect by the inspecting unit is removed from the bundle
of the plurality of threads before the product is shipped, the
collection-amount adjusting unit adjusts an amount of collection by
the collecting unit so that at least one managed quantity for a
plurality of threads selected from a group including a total
number, a total weight, a representative weight, a total outside
diameter value, a representative outside diameter value, a total
surface area, and a representative surface area of the plurality of
threads constituting a bundle product after the thread containing a
defect is removed exceeds a predetermined value.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is the U.S. National Phase application of
PCT/JP2013/051850, filed Jan. 29, 2013, which claims priority to
Japanese Patent Application No. 2012-043208, filed Feb. 29, 2012,
the disclosures of each of these applications being incorporated
herein by reference in their entireties for all purposes.
FIELD OF THE INVENTION
[0002] The present invention relates to a manufacturing method and
a manufacturing device for a bundle product, which performs
manufacturing while adjusting the amount of threads wound so that a
predetermined amount or more of the bundle product obtained by
collectively winding threads continuously running in the
longitudinal direction can be finally obtained.
BACKGROUND OF THE INVENTION
[0003] Threads typified by fibers and hollow fiber membranes, and
the like (hereinafter, also simply referred to as threads) have
been used and actively utilized in various fields and applications
from the past in the form of a thread product formed only by the
threads, or a final product manufactured using the threads as a
main component element. In particular, in many cases, a bundle of
threads obtained by bundling plural threads can significantly
improve performances as a product in comparison with a case of a
single thread. Thus, bundled products formed by the bundle of
threads or final products manufactured by using the bundle product
as a main component element have been increasingly widely used.
[0004] Here, threads attracting attentions as those forming high
functional bundle products include carbon fibers exhibiting high
strength and reduced weight, optical fibers supporting the
information society, and hollow fiber membranes used in various
filters. As described above, these threads usually exhibit
significantly excellent performances when used as a bundled product
rather than when used as a single thread. Thus, their performances
should be guaranteed as the entire bundled product having plural
threads converged therein, rather than as the single thread. For
this reason, extra care should be taken to manufacture and manage
these bundle products.
[0005] A description will be given more specifically by giving an
example of a hollow fiber membrane filter (hereinafter, also
referred to as a "module") used in water treatment such as
wastewater reclamation and desalination of sea water. In general,
the hollow fiber membrane filter has a resin or metallic container,
called a case, accommodating a bundle of hollow fiber membranes.
This filter is designed so as to cause raw water to flow into this
container and pass from the outside (or the inside) of the hollow
fiber membranes to the inside (or the outside) to achieve
filtration effect on the raw water, and to separate the filtered
water from which impurities have been removed and the concentrated
water having impurities concentrated therein, and let them flow out
of the case.
[0006] Although there are various kinds of factors that determine
the filtration performance of this module, the following two
factors are particularly important: the amount of hollow fiber
membrane bundle, and the existence or absence of any defective
hollow fiber membrane (hereinafter, also simply referred to as a
"defective fiber") contained in the filter.
[0007] In general, as for the amount of hollow fiber membrane
bundle, at least one physical quantity is selected from the
following plural physical quantities according to performances
required by customers or applications of the module, which is the
final product. In other words, the physical quantities include, for
example, the number of, the outside diameter of, the surface area
of, and the weight of all the hollow fiber membranes contained in
the module (hereinafter, part or all of these are also referred to
as "managed quantities"). If these managed quantities fall below a
predetermined value, the module cannot fully exert its filtration
performance.
[0008] On the other hand, the defective hollow fiber membrane
includes one having, for example, a scratch, a defect, a foreign
substance, a dent, swelling, or a large hole formed on the surface
thereof, and one having, for example, an excessively thick shape
(thin membrane), an excessively thin shape (thick membrane), a
crushed/flattened shape, a twisted shape, or a clogged shape
(hereinafter, part or all of these are also collectively referred
to as "defect"). If the hollow fiber membrane bundle, constituting
the module, contains such a defective hollow fiber membrane, the
module does not fully exert its performance. Furthermore, only the
small number of defective hollow fiber membranes contained may lead
to a reduction in the product lifetime of the entire module (for
example, if the defective portion breaks when the module is being
used, the raw water enters the filtered water).
[0009] Here, the hollow fiber membrane bundle is generally
manufactured by forming a raw material into a hollow-shaped thread
through an outlet port, applying various processes, winding the
thread using, for example, a rotating reel, and cutting all the
wound threads at a predetermined position. Further, in order to
reduce manufacturing costs, plural hollow fiber membranes are
usually formed in a single line at the same time, and wound up with
the same single rotating reel. Thus, efficiency of the
manufacturing processes improves with increase in the number of
threads that can be manufactured at the same time in a single line
(note that the method of collecting the hollow fiber membrane
bundle is not limited to winding using the rotating reel).
[0010] It should be noted that the amount of winding of the
rotating reel is generally set such that the hollow fiber membranes
can exert a predetermined filtration performance when finally
assembled in the module on the assumption that each of the hollow
fiber membranes is in an ideal state in which the outside diameter,
the surface area, and the weight of each of the hollow fiber
membranes are always equal to design values, and no defect exists
in each of the hollow fiber membranes. This is because, under
conditions changing every moment during manufacturing, it is
difficult to anticipate how the outside diameter, the surface area,
and the weight of the hollow fiber membranes change, and it is not
possible to anticipate where defects occur in the hollow fiber
membranes. As a result, there is no other choice but to set the
ideal states as temporary targets.
[0011] However, in reality, the outside diameter, the surface area,
and the weight of the hollow fiber membranes vary and defects
possibly occur during the processes of manufacturing the hollow
fiber membrane bundle.
[0012] For these reasons, with the conventional method of
manufacturing a hollow fiber membrane bundle, a special worker
adjusts the amount of the hollow fiber membrane bundle, before the
hollow fiber membrane bundle obtained by activating the rotating
reel for a set number of rotations based on the ideal state is
assembled into the case. More specifically, the worker first checks
whether the hollow fiber membrane bundle contains any defective
hollow fiber membrane, and removes the defective hollow fiber
membrane from the hollow fiber membrane bundle if found. Then, the
worker randomly selects several threads from the hollow fiber
membranes remaining in the hollow fiber membrane bundle, measures
the outside diameter or surface area or weight of part of the
selected hollow fiber membrane, and averages the results. After
this, standard values for the managed quantities set in order to
ensure quality of the module serving as the final product are
checked, and hollow fiber membranes, of which managed quantities
are already measured and in which it is already known that no
defect is contained, are replenished to the bundle until the
managed quantities exceed these standard values.
[0013] With the process of manufacturing the hollow fiber membrane
bundle as described above, a bottleneck obviously occurs in the
process in which the worker adjusts the amount of hollow fiber
membranes. Thus, many workers need to be employed to efficiently
manufacture the hollow fiber membrane bundle, which leads to a
significant increase in manufacturing costs. Further, in reality,
it is not possible to manually measure the managed quantities for
all the hollow fiber membranes contained in one hollow fiber
membrane bundle (usually containing several hundreds of hollow
fiber membranes). Thus, adjustment of the amount of hollow fiber
membranes has to be made only on the basis of measured values
(representative values) obtained through sampling of hollow fiber
membranes. However, with the method as described above, the actual
performance of the hollow fiber membrane bundle after adjustment
may be not adequate.
[0014] As for measures for solving the problems as described above,
configurations of Patent Documents 1, 2, and 3 are proposed.
[0015] First, Patent Document 1 describes automatically detecting
defects occurring in threads and determining types of the defects
while the threads are running in manufacturing processes; cutting
and removing length according to the type of the defect while the
thread is being running; and joining the cut portions.
[0016] Next, Patent Document 2 describes that, if any abnormality
in the diameter of thread is automatically detected when the thread
is returned from a thread bobbin on the unwind side to a thread
cheese on the winding side, length to be cut is calculated on the
basis of the degree of the abnormality, and by reversing the
rotation of the cheese, the portion to be cut is unwound to cut the
target portion.
[0017] Next, Patent Document 3 describes that, when a visual
inspection worker finds a defective portion and cuts off the
defective portion during production (winding) of paper sheets,
length that has been cut is automatically detected on the basis of
a diameter of the roll before and after the defective portion is
cut, and the amount of winding is controlled so as to compensate
the portion that has been cut so that the thread with a specified
length can be wound.
[0018] However, with the methods described in Patent Documents 1
and 2, by automatically performing measurement and inspection
during running of the thread, it is possible to eliminate the
special worker, and cut off the defective portion. However, these
methods are performed on the assumption that a single thread runs
in a single line. More specifically, if a defective portion of a
certain thread is cut off in the case where two or more threads run
in a single line, the length of this thread differs from the
lengths of the other threads, so that these threads cannot be wound
around the same rotating reel. If these threads are required to be
wound around the same reel, when a defective portion is cut off
from a certain thread, it may be possible to cut off the same
length of a normal portion from threads that do not have any defect
and are manufactured at the same time. However, with this method,
manufacturing yields reduces. Further, Patent Document 1 or 2 does
not propose a method of correcting the final managed quantities for
the hollow fiber membrane bundle after the defective portion is cut
off.
[0019] Patent Document 3 relates to a paper sheet instead of a
thread, and obtains a length of a portion to be cut off on the
basis of the roll diameter before and after the defective portion
is cut off to correct the amount of winding so that the length of
the paper sheet contained in the final product meets the
requirements. However, as in Patent Documents 1 and 2, it is
difficult to apply this method in the case where plural products
are manufactured in a single line at the same time. Further, in
Patent Document 3, a length of the paper sheet is the only managed
quantity. However, in the case where high-functional final product
such as the hollow fiber membrane bundle are manufactured, it is
essential to manage other values such as an outside diameter, a
surface area, and a weight as described above.
PATENT LITERATURE
[0020] PTL 1: Japanese Unexamined Patent Application Laid-Open No.
H3-120170 [0021] PTL 2: Japanese Unexamined Patent Application
Laid-Open No. H10-310330 [0022] PTL 3: Japanese Unexamined Patent
Application Laid-Open No. S63-127967
SUMMARY OF THE INVENTION
[0023] An object of the present invention is to provide a
manufacturing method and a manufacturing device for a bundle
product, which improve inspection quality and manufacturing
efficiency in the case where a desired amount of two or more
threads continuously running in parallel are collected while being
inspected.
[0024] In order to solve the problem described above, the
manufacturing method for a bundle product according to the present
invention includes any of the following configurations (1) to (9)
described below.
(1) A manufacturing method for a bundle product, including the
steps of: inspecting two or more threads continuously running in
parallel in a longitudinal direction; collecting the threads; and
cutting all the threads collected at a predetermined position after
completion of collecting, to obtain a bundle product having a
plurality of threads converged into a bundle, in which
[0025] an amount of collection in the collecting step is adjusted
on the basis of inspection results obtained in the inspecting step
so that at least one managed quantity for a plurality of threads
selected from a group including a total number, a total weight, a
representative weight, a total outside diameter value, a
representative outside diameter value, a total surface area, and a
representative surface area of the plurality of threads
constituting the bundle product exceeds a predetermined value.
(2) The manufacturing method for a bundle product according to (1)
described above, in which the collecting step is a winding and
collecting step of collecting the threads during rotation. (3) The
manufacturing method according to (1) described above, in which the
collecting step is a cutting and collecting step of collecting the
threads while cutting the threads to a certain length. (4) The
manufacturing method according to (1) described above, in which the
collecting step is a turn-around collecting step of collecting the
threads while turning around the threads at a certain length. (5)
The manufacturing method for a bundle product according to any of
(1) to (4) described above, in which the threads are hollow fiber
membranes. (6) The manufacturing method for a bundle product
according to any of (1) to (5) described above, in which the
managed quantity for the plurality of threads is the total surface
area of the plurality of threads constituting the bundle product.
(7) The manufacturing method for a bundle product according to any
of (1) to (5) described above, in which the managed quantity for
the plurality of threads is the representative surface area of the
plurality of threads constituting the bundle product. (8) The
manufacturing method for a bundle product according to (6) or (7)
described above, in which, in the inspecting step, outside
diameters of the threads are measured, and surface areas of the
threads are calculated on the basis of the obtained measured values
of the outside diameters. (9) The manufacturing method for a bundle
product according to any of (1) to (8) described above, further
including the step of:
[0026] removing a thread determined to contain a defect in the
inspecting step from the bundle of the plurality of threads, in
which
[0027] an amount of collection in the collecting step is adjusted
so that at least one managed quantity for a plurality of threads
selected from a group including a total number, a total weight, a
representative weight, a total outside diameter value, a
representative outside diameter value, a total surface area, and a
representative surface area of the plurality of threads
constituting a bundle product after the thread containing the
defect is removed in the removing step exceeds a predetermined
value.
[0028] Further, a device for manufacturing a bundle product
according to the present invention includes any of the following
configurations (10) to (13).
(10) A manufacturing device for a bundle product including an
inspecting unit that inspects two or more threads continuously
running in parallel in a longitudinal direction, a collecting unit
that collects the threads, and a cutting unit that, after
completion of collecting, cuts all the collected threads at a
predetermined position, to obtain a bundle product having a
plurality of threads converged into a bundle, in which
[0029] the manufacturing device further includes a
collection-amount adjusting unit that can adjust an amount of
collection by the collecting unit on the basis of inspection
results obtained by the inspecting unit so that at least one
managed quantity for a plurality of threads selected from a group
including a total number, a total weight, a representative weight,
a total outside diameter value, a representative outside diameter
value, a total surface area, and a representative surface area of
the plurality of threads constituting the bundle product exceeds a
predetermined value.
(11) The manufacturing device for manufacturing a bundle product
according to (10) described above, in which the threads are hollow
fiber membranes. (12) The manufacturing device for manufacturing a
bundle product according to (10) or (11) described above, in which
the inspecting unit includes means for calculating surface areas of
the threads on the basis of a measured value of an outside diameter
obtained by the inspecting unit that measures outside diameters of
the threads. (13) The manufacturing device for manufacturing a
bundle product according to any of (10) to (12) described above, in
which
[0030] on the assumption that a thread determined to contain a
defect by the inspecting unit is removed from the bundle of the
plurality of threads before the product is shipped, the
collection-amount adjusting unit adjusts an amount of collection by
the collecting unit so that at least one managed quantity for a
plurality of threads selected from a group including a total
number, a total weight, a representative weight, a total outside
diameter value, a representative outside diameter value, a total
surface area, and a representative surface area of the plurality of
threads constituting a bundle product after the thread containing a
defect is removed exceeds a predetermined value.
[0031] With the manufacturing method for a bundle product according
to the present invention, it is possible to measure all the managed
quantities for all the plural threads during running from the start
of collection to the end. This makes it possible to control the
amount of winding in a collecting step so that each of the managed
quantities exceeds standard values, and to reliably ensure the
quality of the bundle product finally obtained. Thus, it is
possible to eliminate the need for a worker to measure the managed
quantities after the bundle product is obtained and replenish
normal threads to the bundle product. Further, since all the
managed quantities can be measured for all the plural threads,
which is impossible for the worker to do, it is possible to
minimize the risk that actual performance of the bundle product
finally obtained is insufficient.
[0032] Further, with the present invention, it is possible to
inspect all the plural threads during running as to whether any
defect exists, and further, it is possible to control the amount of
winding in a collecting step while considering that, if any defect
is found, this defective portion is removed later from the bundle
of threads. Thus, it is possible to eliminate the need for the
worker to inspect the bundle of threads after the bundle product is
obtained and replenish normal threads to the bundle product.
[0033] Yet further, according to the present invention, it is
assumed that the defective portion is removed once after the bundle
of threads is obtained. Thus, if the number of defects occurring
increases, there is no need to stop the line, and hence,
manufacturing efficiency does not deteriorate.
[0034] The manufacturing device for a bundle product according to
the present invention is one that can preferably implement the
manufacturing method for a bundle product according to the present
invention described above, and is one that can ensure the quality
of threads constituting the bundle product and improve
manufacturing efficiency in the case where two or more threads are
caused to continuously run in parallel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIGS. 1(a) and 1(b) are schematic views each illustrating an
example of an embodiment (winding and collecting step) of a
manufacturing device according to the present invention, in which
FIG. 1(a) is a side view, and FIG. 1(b) is a top view.
[0036] FIGS. 2 (a) to 2 (c) are schematic views each illustrating
an example of an embodiment (cutting step) of the manufacturing
device according to the present invention, and illustrating
processes of operation with time.
[0037] FIGS. 3(a) and 3(b) are schematic views exemplarily
illustrating images each including hollow fiber membranes with
various outside diameters.
[0038] FIGS. 4(a) to 4(d) are schematic views exemplarily
illustrating images each including hollow fiber membranes which are
defective fibers.
[0039] FIG. 5 is a schematic view exemplarily illustrating a flow
controlling a collecting step on the basis of the total amount of
managed quantities.
[0040] FIG. 6 is a schematic view exemplarily illustrating a flow
controlling a collecting step on the basis of representative
amounts of managed quantities.
[0041] FIGS. 7(a) and 7 (b) are schematic views each illustrating
an example of another embodiment (cutting and collecting step) of
the manufacturing device according to the present invention, in
which FIG. 7 (a) is a side view, and FIG. 7 (b) is a top view.
[0042] FIGS. 8(a) and 8(b) are schematic views each illustrating an
example of another embodiment (turn-around collecting step) of the
manufacturing device according to the present invention, in which
FIG. 8 (a) is a side view, and FIG. 8(b) is a top view.
[0043] FIGS. 9(a) and 9(b) are schematic views each illustrating an
example of an embodiment (a marker is provided in the winding and
collecting step) of the manufacturing device according to the
present invention, in which FIG. 9(a) is a side view, and FIG. 9(b)
is a top view.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0044] A manufacturing device for a bundle product according to an
embodiment of the present invention includes at least an inspecting
unit, a collecting unit, a cutting unit and a collection-amount
adjusting unit for bundle products. Of these units, the collecting
unit and the cutting unit may be configured as units independent
from each other, or configured as a cutting and collecting unit
having both of a collecting function and a cutting function.
Further, the manufacturing device for a bundle product may further
include a marker unit.
[0045] The inspecting unit includes measuring and inspecting means
and an inspection controlling mechanism, and is one that performs
measurements and inspection on two or more threads continuously
running in parallel in the longitudinal direction, as to managed
quantities selected from the total amounts (total number, total
weight, total outside diameter, total surface area) and
representative amounts (representative weight, representative
outside diameter, representative surface area). Further, the
inspecting unit can inspect the threads as to whether any defect
exists in the threads. The marker unit includes a marker head and a
marker controlling mechanism, and puts a mark on a thread
determined to be abnormal in collaboration with the inspecting
unit.
[0046] The collecting unit unites plural threads, which
continuously run, while collecting the threads, and can adjust the
amount of collection per bundle product in collaboration with the
inspecting unit and the collection-amount adjusting unit. Examples
of the independent collecting unit include a winding and collecting
device that collects the threads while rotating, and a turn-around
collecting device that collects the threads while turning around
the threads at a predetermined length. The cutting unit cuts all
the threads collected by the collecting unit at a predetermined
position.
[0047] Further, the cutting and collecting unit has a function of
collecting plural threads, a function of adjusting the amount of
collection, and a cutting function. An example of the cutting and
collecting unit includes a cutting and collecting device that
collects the threads while cutting the threads to a certain
length.
[0048] The collection-amount adjusting unit is a controlling unit
that adjusts the amount of collection in the collecting unit so
that the managed quantities for the plural threads measured by the
inspecting unit exceed a predetermined value in the bundle product,
and further, adjusts the amount of collection of the threads in the
collecting unit so as to compensate for the managed quantities
corresponding to the threads determined to be abnormal by the
inspecting unit and removed from the bundle product.
[0049] A manufacturing method for a bundle product according to an
embodiment of the present invention includes at least an inspecting
step, a collecting step, and a cutting step. Of these steps, the
collecting step and the cutting step may be configured as steps
independent from each other, or configured as a cutting and
collecting step that performs both of the operations.
[0050] In the inspecting step, measurement and inspection are
performed on two or more threads continuously running in parallel
in the longitudinal direction, as to managed quantities selected
from the total amounts (total number, total weight, total outside
diameter, and total surface area) and representative amounts
(representative weight, representative outside diameter, and
representative surface area).
[0051] In the collecting step, plural threads continuously running
are collected while being united. On the basis of the managed
quantities measured in the inspecting step, it is possible to
determine whether standard values set for the bundle product are
exceeded, and adjust the amount of collection of the threads.
Further, if it is detected in the inspection step that an abnormal
thread (defective fiber) exists, it is possible to further adjust
the amount of collection of the threads so as to compensate for the
managed quantities corresponding to the defective fiber removed
from the bundle product.
[0052] In the cutting step, all the threads collected in the
collecting step are cut at a predetermined position. Further, in
the cutting and collecting step, plural threads are collected and
cut in one step.
[0053] With the manufacturing method for a bundle product according
to the present invention, it is possible to stably manufacture
high-quality bundle products by using the manufacturing device for
a bundle product described above.
[0054] An example of the bundle product may include a hollow fiber
membrane bundle used as an ultrafiltration membrane, a
microfiltration membrane, a gas separation membrane, a
pervaporation membrane, and a dialysis membrane. The hollow fiber
membrane bundle is used, for example, in water treatment,
artificial kidney, or concentration of valuables in various
industrial processes. Note that the bundle product is not limited
to the hollow fiber membranes as described above, and any bundle
product may be possible, provided that the bundle product is a
thread product such as fiber for clothing, carbon fiber, optical
fiber, steel wire, and medical catheter, which has a structure in
which plural threads can be substantially manufactured in parallel
at the same time.
[0055] Embodiments according to the present invention will be
described below with reference to the drawings by taking a hollow
fiber membrane bundle as an example. Note that these embodiments do
not limit the present invention.
Embodiment 1
[0056] The first embodiment of the manufacturing device for a
bundle product according to the present invention includes an
inspecting unit, a winding and collecting unit, a cutting unit, and
a collection-amount adjusting unit. FIGS. 1(a) and 1(b) illustrate
embodiments of the inspecting unit, the winding and collecting
unit, and the collection-amount adjusting unit. FIGS. 2(a), 2(b)
and 2(c) illustrate an embodiment of the cutting unit.
[0057] In FIGS. 1(a) and 1(b), reference numeral 10 represents a
single thread of a hollow fiber membrane; 11 represents a
united-thread hollow fiber membrane formed by uniting plural single
threads; 12 represents a united-thread hollow fiber membrane bundle
collected; 20 represents a measuring and inspecting head; 21
represents a measurement and inspection controlling mechanism; 22
represents a winding and collecting device; 23 represents a reel;
231, 232, and 233 represent a first reel position, a second reel
position, and a third reel position, respectively; 24 represents a
winding and collection controlling mechanism; 25 represents a
united-thread guide; 26 represents a roll; and 37 represents a
thread path guide. The inspecting unit includes at least the
measuring and inspecting head 20, and the measurement and
inspection controlling mechanism 21. The collecting unit includes
at least the winding and collecting device 22, the reel 23, the
united-thread guide 25, the roll 26, and the thread path guide 37.
The collection-amount adjusting unit is formed by the winding and
collection controlling mechanism 24.
[0058] Note that FIG. 1(a) is a side view, and FIG. 1(b) is a top
view. The measuring and inspecting head 20, the measurement and
inspection controlling mechanism 21, and the winding and collection
controlling mechanism 24, which relate to control signals, are
illustrated only in FIG. 1(a).
[0059] Furthermore, in FIGS. 2(a), 2(b) and 2(c), which illustrate
the cutting unit, reference numeral 13 represents a hollow fiber
membrane bundle; 40 represents a cutter; 401 represents a cutter at
a cutting position; 41 represents a binding unit; 42 represents a
hanging rope; 43 represents a crane rail; and 44 represents a
crane.
[0060] The hollow fiber membrane to be manufactured in the present
invention is basically collected in the form of a united-thread
hollow fiber membrane 11 obtained by uniting single threads 10 of
the hollow fiber membranes as illustrated in FIG. 1(b). However, a
single thread 10 may be collected as it is, which raises no
problem. Furthermore, also as the method of collection, the
united-thread hollow fiber membrane 11 or the single thread 10 may
be collected with plural collecting means (for example, plural reel
positions) at the same time or may be collected sequentially. Note
that, for ease of understanding, the following descriptions will be
given on the cases assuming the united-thread hollow fiber membrane
11.
[0061] Here, the material for the hollow fiber membrane includes,
for example, organic polymers such as polycarbonate, polyolefin,
polyamide, polyimide, cellulose, polysulfone, polyethersulfone,
polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride,
and polyetherketone, and ceramics such as alumina, zirconia,
titania, and silicon carbide.
[0062] As illustrated in FIGS. 1(a) and 1(b), the thread path guide
37 specifies running positions for the plural single threads 10 of
the hollow fiber membranes conveyed from the upstream processes,
and the single threads are united by the united-thread guide 25 to
form the united-thread hollow fiber membrane 11, which is wound
with the reel 23 of the winding and collecting device 22 while
being pressed against the roll 26 to form the united-thread hollow
fiber membrane bundle 12 (note that, in the descriptions of the
present invention, an example is given in which three single
threads 10 of the hollow fiber membranes are united, but the number
of single threads 10 of the hollow fiber membranes to be united is
not limited to three). Here, the reel 23 may have plural winding
positions such as the first reel position 231, the second reel
position 232, and the third reel position 233 as illustrated in
FIG. 1(b), and can wind the united-thread hollow fiber membrane 11
at these positions sequentially or simultaneously (as described
above, this can be applied not only to the united-thread hollow
fiber membrane 11 but also to the single thread 10 of the hollow
fiber membrane). Further, the reel 23 is configured so as to be
movable in the same direction as that of the rotational axis. With
this movement, the united-thread hollow fiber membrane 11 is wound
uniformly in the width direction within the first reel position 231
(second reel position 232, third reel position 233), or after the
completion of winding, the reel position is moved to the next
position to successively continue the winding. Note that in this
embodiment, an example is given in which the number of reel
positions is three. However, the number of reel positions is not
limited to three. Further, an example is given in which the reel 23
is moved in the same direction as that of the rotational axis.
However, the same effect can be obtained also with a method in
which the reel 23 is fixed and the united-thread guide 25 is
moved.
[0063] Here, the winding and collection controlling mechanism 24
controls start and stop of rotation of the winding and collecting
device 22, the rotational speed, movement of the reel 23 in the
same direction as that of the rotational axis, movement of the reel
position after the completion of winding, the number of rotations
of the reel, 23 and other operations. Furthermore, the number of
rotations of the reel 23 is controlled so that the predetermined
amount of the united-thread hollow fiber membrane bundle 12 can be
obtained. Then, after the predetermined amount thereof is obtained,
a completion operation such as stop of the reel or automatic
movement to the next reel position is controlled.
[0064] Furthermore, the inspecting unit according to an embodiment
of the present invention includes the measuring and inspecting head
20 that monitors the single thread of the hollow fiber membrane,
and the measurement and inspection controlling mechanism 21 that
processes information obtained by the measuring and inspecting head
20 to actually measure the outside diameter of the thread or check
existence of defect. The measurement and inspection controlling
mechanism 21 and the winding and collection controlling mechanism
24 are configured so that information can be communicated to each
other. Note that, for the measuring and inspecting head 20, it may
be possible to employ, for example, a general-purpose digital
camera, an analog camera, a lens for general-purpose cameras, or a
shape measurement sensor using an LED illumination or laser light.
Further, as for the measurement and inspection controlling
mechanism 21, it may be possible to employ a system configured by
installing, for example, an image capturing board, a signal
processing board, a communication board, signal processing
software, and system controlling software to a general-purpose PC,
or a commercially available image inspection system. Further, it
may be possible to integrally form the winding and collection
controlling mechanism 24 and the measurement and inspection
controlling mechanism 21. Operations of parts associated with these
control signals will be described in detail later.
[0065] After the reel 23 finishes winding the predetermined amount
of the united-thread hollow fiber membrane bundle 12, the
united-thread hollow fiber membrane bundle 12 is cut at a portion
joined with the united-thread hollow fiber membrane 11, and
conveyed to the next step together with the reel 23. Note that,
after this, in the case where the united-thread hollow fiber
membrane 11 is continuously conveyed from the upstream side, a new
empty reel 23 is immediately set, and winding of the united-thread
hollow fiber membrane 11 is started, thereby continuing
manufacturing.
[0066] Next, the cutting step will be described with reference to
FIGS. 2(a) to 2(c). Here, for ease of understanding, a description
will be given only of a case where the number of the reel position
is one. However, in the case where there are plural reel positions,
it is only necessary to increase the following procedure by the
number of the reel positions. As illustrated in FIG. 2(a), the reel
23 is first fixed with respect to the cutter 40. Then, in the
vicinity of the cutter 40, the position corresponding to the
upstream side in the collecting step is bound to a hanging rope 42
using a binding unit 41. The hanging rope 42 is configured so as to
be wound up by a crane 44 provided at a crane rail 43. After this,
as illustrated in FIG. 2(b), by moving the cutter 40 to the cutting
position 401, the united-thread hollow fiber membrane bundle 12 is
collectively cut to give a hollow fiber membrane bundle 13. The
hollow fiber membrane bundle 13 has an end portion bound with the
hanging rope 42 using the binding unit 41, and hence, is gradually
taken out from the reel 23 with the crane 44 being operated so as
to be rolled up. Finally, as illustrated in FIG. 2(c), the hollow
fiber membrane bundle 13 is fully taken out from the reel 23, and
the crane 44 is moved along the crane rail 43, whereby the hollow
fiber membrane bundle 13 is conveyed to the next removing step.
Note that the removing step is a step of removing a thread
(defective thread) determined to contain a defect in the inspecting
step from the hollow fiber membrane bundle 13.
[0067] These are basic descriptions of the manufacturing method of
the hollow fiber membrane bundle 13. Next, a method of controlling
the collecting step will be described.
[0068] As described above, the managed quantities for the hollow
fiber membrane bundle 13 are specified on the basis of applications
of a module, which is a final product, or performance required by
customers for the module. The managed quantities include, for
example, the total number, the total weight, the representative
weight, the total outside diameter value, the representative
outside diameter value, the total surface area, and the
representative surface area concerning all the hollow fiber
membranes contained in the hollow fiber membrane bundle 13, which
is to be assembled in the module sometime in the future.
[0069] If the hollow fiber membranes are manufactured in an ideal
state where the shapes or weights of the hollow fiber membrane do
not vary, and no defective fiber exists therein, the amount of
collection in the collecting step can be determined on the basis of
quality standard values, and correction during manufacturing is not
required. However, actually, variation in manufacturing occurs, and
if a defective fiber exists due to external disturbances occurring
during manufacturing processes, this defective fiber has to be
removed from the hollow fiber membrane bundle 13. Thus, the present
invention is characterized in that, on the assumption that
variation in manufacturing occurs or a defective fiber exists, the
collecting step is preferably controlled during manufacturing so
that the hollow fiber membrane bundle 13 exceeds predetermined
standard values after the collecting step and the removing step.
Note that it is necessary that the managed quantities for the
hollow fiber membrane bundle 13 at least exceed the standard
values. However, it is more preferable to perform control so as to
end the collection step at a time when these managed quantities
exceed the standard values because such control eliminates wasteful
manufacturing.
[0070] Variations in manufacturing of the hollow fiber membranes
and the existence of the defective fiber are monitored by the
measuring and inspecting head 20 and the measurement and inspection
controlling mechanism 21 as illustrated in FIG. 1(a). Here,
descriptions will be given by taking an example in which a
general-purpose digital-camera-type image inspection system is used
as the measuring and inspecting head 20 and the measurement and
inspection controlling mechanism 21.
[0071] The digital camera serving as the measuring and inspecting
head 20 repeatedly captures, at temporal intervals, images of the
plural single threads 10 of the hollow fiber membranes conveyed in
parallel without failing to capture images of even a part of the
hollow fiber membranes, and sends the captured images to the
measurement and inspection controlling mechanism 21. FIGS. 3(a) and
3(b), and FIGS. 4(a) to 4(d) illustrate examples of images captured
and sent.
[0072] In FIGS. 3(a) and 3(b), reference numeral 50 represents an
image; 51, 52, 53, and 55 represent images of hollow fiber
membranes having an outside diameter of .beta.; 54 represents an
image of hollow fiber membrane having an outside diameter of
.alpha.; and 56 represents an image of hollow fiber membrane having
an outside diameter of .gamma., where the outside diameters have a
relationship of .alpha.<.beta.<.gamma., .beta. is an outside
diameter equal to a design value for manufacturing, .alpha. is the
lower limit value for the outside diameter, and .gamma. is the
upper limit value for the outside diameter. Note that, because the
amount of raw material per unit length of the hollow fiber membrane
can be considered to be constant, the thickness of each membrane is
thin in the case where the outside diameter is larger than the
design value, whereas the thickness of each membrane is thick in
the case where the outside diameter is smaller. In the case where
the thickness is small, the membrane is more likely to break during
the time when the hollow fiber membrane is used as a filtration
membrane. On the other hand, in the case where the thickness is
large, excessive pressure is required for filtration, and the flow
path inside the hollow portion is narrow, which makes it difficult
to obtain the amount of flow required for filtration and makes
clogging more likely to occur.
[0073] In FIGS. 4(a) to 4(d), reference numeral 57 represents an
image of a defective hollow fiber membrane (scratch); 58 represents
an image of a defective hollow fiber membrane (defect); 59
represents an image of a defective hollow fiber membrane (foreign
substance); 60 represents an image of a defective hollow fiber
membrane (dent); 61 represents an image of a defective hollow fiber
membrane (swelling); 62 represents an image of a defective hollow
fiber membrane (large hole); 63 represents an image of a defective
hollow fiber membrane (excessively thin; less than the lower limit
value .alpha. for the outside diameter); 64 represents an image of
a defective hollow fiber membrane (excessively thick; more than the
upper limit value .gamma. for the outside diameter); 65 represents
an image of a defective hollow fiber membrane (crushed); 66
represents an image of a defective hollow fiber membrane (twisted);
67 represents an image of a defective hollow fiber membrane
(clogged); and 68 represents a state in which no image of a hollow
fiber membrane is captured because of cutting of a thread.
[0074] Note that, in these images, it is assumed that the captured
image resolution in the width direction (XD direction) of the
hollow fiber membrane in the image is X .mu.m/pix, and the captured
image resolution in the longitudinal direction (YD
direction=direction in which a hollow fiber membrane is conveyed)
of the hollow fiber membrane is Y .mu.m/pix. The captured image
resolution is defined as an amount indicating the actual size in
the three-dimensional world to which each pixel (pix) constituting
the image corresponds, and a unit thereof is defined as the size
(.mu.m/pix) per pixel (pix).
[0075] If the quality of the hollow fiber membrane is managed
during manufacturing, it can be considered that there are following
two types of managed quantities for the hollow fiber membrane used
as indexes: the total amount (total number, total weight, total
outside diameter, and total surface area) and the representative
amount (representative weight, representative outside diameter, and
representative surface area). The former type is one for adjusting
the amount of collection of the hollow fiber membrane bundle while
considering all pieces of information on the managed quantities for
the hollow fiber membrane being manufactured, and is ideal from the
viewpoint of the quality management. However, the measurement and
inspection controlling mechanism 21 has to carry a huge burden,
which results in disadvantages in equipment such as the necessity
to use a high-speed expensive calculator, or the necessity for
plural calculators to share the system. On the other hand, the
latter type is one in which the measurement and inspection
controlling mechanism 21 measures, once or plural times, a specific
portion of the hollow fiber membrane being manufactured in
accordance with predetermined conditions, and adjusts the amount of
collection using, as indexes, the representative amounts calculated
on the basis of the measurement results, and this type can be
configured with simple equipment. However, in order to realize
sufficient quality management, it is required that variation in
quality of the hollow fiber membrane to be manufactured should be
sufficiently small. In other words, it is preferable to adopt the
former type in the case where variation in quality of the hollow
fiber membrane to be manufactured is expected to be large, and
adopt the latter type in the case where the variation is expected
to be small.
[0076] On the basis of the facts described above, with reference to
a process flow in FIG. 5, a description will be first given of a
case where the total amount is used as the managed quantity for the
hollow fiber membrane.
[0077] Where the collecting step starts, first in Step 11, a
program in the measurement and inspection controlling mechanism 21
is initialized. At this time, types and the standard values of the
managed quantities, which are preset to be used in the quality
management, are read into the program. Next, in Step 12, the
measurement and inspection controlling mechanism 21 instructs the
winding and collection controlling mechanism 24 to rotate the reel
23, and the reel 23 starts to rotate. Then, in Step 13, while the
reel 23 rotates one turn, the managed-quantity sum total value for
each of the plural single threads 10 of the hollow fiber membranes
conveyed in parallel is calculated, and then, the managed-quantity
sum total value is corrected on the basis of the judgment results
for the defective fiber (details thereof will be described later).
Then, in Step 14, the managed-quantity sum total values are added
up until the current turn, thereby obtaining the total amount of
the managed quantities. Then, in Step 15, it is determined whether
the total amount of the managed quantities exceeds a standard
value. If the total amount of the managed quantities does not
exceed the standard value, the process returns to Step 12, whereas,
if the total amount exceeds the standard value, the process moves
to Step 16 (if the total amount exceeds the standard value, it
means that a predetermined winding of the united-thread hollow
fiber membrane bundle 12 is completed at this reel position). Next,
in Step 16, it is determined whether winding of the hollow fiber
membrane is moved to another reel position. If the winding is moved
to another reel position, the winding and collecting device 22 is
operated to move the hollow fiber membrane to the next reel
position, and the process returns to Step 11. If the winding is not
moved, the process proceeds to Step 17. Next, in Step 17, the reel
is stopped, and winding of a predetermined united-thread hollow
fiber membrane bundle 12 for all of the reel positions is
completed.
[0078] Details of Step 13 will be described. First, in Step 13a,
images 50 of the plural single threads 10 of the hollow fiber
membranes conveyed in parallel are captured with a digital camera
at time intervals, and the images 50 are sent to a signal
processing unit of a digital-camera-type image inspection system.
The timing at which images of the single threads 10 of the hollow
fiber membranes are captured at time intervals is determined so as
to capture all the images of the hollow fiber membranes conveyed
without failing to capture images of even a part thereof. For
example, the timing for capturing the images may be determined by
considering, for example, the width of the image that one shot of
image-capturing covers and the speed at which the hollow fiber
membranes are conveyed.
[0079] Next, in Step 13b, the signal processing unit individually
recognizes the images 51 to 67 of the plural single thread hollow
fiber membranes in the images 50. Note that, also in the case where
cutting of the thread occurs, the occurrence of the cutting 68 of
the thread is recognized by checking the portion of the hollow
fiber membrane where an image is supposed to be captured. Next, in
Step 13c, the managed quantities are calculated for each of the
single threads 10 of the hollow fiber membranes. Note that,
although the method of calculating the managed quantities will be
described later, all the managed quantities are calculated as 0
(zero) for the cutting of the thread.
[0080] Next, in Step 13d, all the managed quantities measured until
the present time on the basis of the images sent at time intervals
are added up to obtain the managed-quantity sum total value for
each of the single threads 10 of the hollow fiber membranes. Note
that the managed quantities in Step 13d are added up on the
assumption that images for one turn of the reel are captured
separately plural times, and hence, this does not apply to a case
where one image for one turn of the reel is captured only once.
[0081] Next, in Step 13e, it is checked whether any of defective
hollow fiber membranes 57 to 67 exists in the image. If none of
defective hollow fiber membrane 57 to 67 exists, the process
proceeds directly to next Step 13h. On the other hand, if any of
defective hollow fiber membranes 57 to 67 exists, the process
proceeds to next Step 13f. In Step 13f, a removing flag is
generated in information on the defective fiber. Usage of the
removing flag will be described later. Next, in Step 13g, the
managed-quantity sum total value calculated in Step 13d is
corrected. More specifically, the defective fiber in which a defect
has been found is removed in the removing step, and hence, this
managed quantity needs to be excluded from the managed-quantity sum
total value during this turn of the reel. Next, in Step 13h, it is
determined whether the reel has completed rotating one turn. For
this determination, it is only necessary to receive a completion
signal from the winding and collection controlling mechanism 24. If
the reel has not yet completed rotating one turn, the process
returns to Step 13a, whereas, if completed rotating one turn, the
process proceeds to Step 14.
[0082] Next, with reference to a process flow in FIG. 6, a
description will be given of a case where representative amounts
are used as the managed quantities for the hollow fiber
membranes.
[0083] When the collecting step starts, a program in the
measurement and inspection controlling mechanism 21 is first
initialized in Step 21. At this time, preset types and standard
values of managed quantities used for the quality management are
read into the program, and a temporary value of the number of
rotations of the reel 23 is set. Then, in Step 22, the measurement
and inspection controlling mechanism 21 instructs the winding and
collection controlling mechanism 24 to rotate the reel 23, and the
reel 23 starts to rotate. Then, in Step 23, the managed-quantity
sum total value is calculated for each of the plural single threads
10 of the hollow fiber membranes conveyed in parallel, the target
number of rotations is determined in accordance with conditions for
obtaining the representative amounts, and then, the target number
of rotations is corrected on the basis of the determination results
on the defective fiber (details thereof will be described later).
Then, in Step 24, when the reel 23 rotates one turn, the actual
number of rotations is incremented by one. Next, in Step 25, it is
determined whether the actual number of rotations exceeds the
target number of rotations. If the actual number of rotations does
not exceed the target number of rotations, the process returns to
Step 22, whereas, if it exceeds the target number of rotations, the
process proceeds to Step 26 (if it exceeds the target number of
rotations, this means that a predetermined winding of the
united-thread hollow fiber membrane bundle 12 is completed at this
reel position). Next, in Step 26, it is determined whether winding
of the hollow fiber membrane is moved to another reel position. If
the winding is moved, the winding and collecting device 22 is
operated to move the hollow fiber membrane to the next reel
position, and the process returns to Step 21, and if the winding is
not moved, the process proceeds to Step 27. Next, in Step 27, the
reel is stopped, and winding of a predetermined united-thread
hollow fiber membrane bundle 12 for all of the reel positions is
completed.
[0084] Details of Step 23 will be described. First, in Step 23a,
images 50 of the plural single threads 10 of the hollow fiber
membranes conveyed in parallel are captured with a digital camera,
and the images 50 are sent to a signal processing unit of a
digital-camera-type image inspection system. Next, in Step 23b, the
signal processing unit individually recognizes the images 51 to 67
of the plural single thread hollow fiber membranes in the images
50. Note that, also in the case where cutting of the thread occurs,
the occurrence of the cutting 68 of the thread is recognized by
checking the portion of the hollow fiber membrane where an image is
supposed to be captured. Next, in Step 23c, it is checked whether
the target number of rotations is determined. If it is determined,
the process moves to Step 23g. If it is not determined, the process
proceeds to Step 23d. Next, in Step 23d, the managed quantities are
calculated for each of the single threads 10 of the hollow fiber
membranes, and the calculated value is stored in a numerical
buffer. Note that, although the method of calculating the managed
quantities will be described later, all the managed quantities are
calculated as 0 (zero) for the cutting of, the thread. Next, in
Step 23e, it is checked whether data on the managed quantities
necessary to calculate the representative amounts are available. If
the data are available, the process proceeds to Step 23f, whereas,
if the data are not yet available, the process moves to Step 23g.
Next, in Step 23f, the data on the managed quantities are processed
and calculated in accordance with conditions for calculating the
representative amounts and the standard values to determine the
target number of rotations, and the temporary number of rotations
is rewritten with the target number of rotations. Next, in Step
23g, it is checked whether any of the defective hollow fiber
membranes 57 to 67 exists in the image. If it does not exists, the
process proceeds directly to next Step 23j. On the other hand, if
it exists, the process proceeds to next Step 23h. In Step 23h, a
removing flag is generated in information on the defective fiber.
Usage of the removing flag will be described later. Next, in Step
23i, the target number of rotations calculated in Step 23f is
corrected. More specifically, the defective fiber in which a defect
has been found is removed in the removing step, and hence, with the
current target number of rotations, there is a possibility that it
is not possible to satisfy the standard values at the end. In such
a case, the target number of rotations needs to be increased. Next,
in Step 23j, it is determined whether the reel has completed
rotating one turn. For this determination, it is only necessary to
receive a completion signal from the winding and collection
controlling mechanism 24. If the reel has not yet completed
rotating one turn, the process returns to Step 23a, whereas, if the
reel has already completed rotating one turn, the process proceeds
to Step 24.
[0085] Here, a supplementary description will be given of Step 23f.
The conditions for calculating the representative amounts used in
Step 23 should be appropriately set according to the degree of
variations occurring during manufacturing processes, the degree of
the quality management for product types to be manufactured, or
quality requirements from customers. For example, it is preferable
to use, an average value of all the managed quantities for all the
plural threads for the first turn of the reel 23, or an average
value of specific single threads, or an average value of these
values for plural turns. However, the way of determining the
conditions for calculating the representative amounts is not
limited to those described above.
[0086] As for common items between the two methods, which are the
total amount and the representative amounts used as indexes of the
managed quantities for the hollow fiber membrane, the first common
item is a characteristic as to the way of obtaining the managed
quantities. More specifically, the managed quantity is basically
obtained in a fine performance with the maximum captured-image
resolution (X .mu.m/pix, Y .mu.m/pix) described above (primary
managed quantity). However, it may be possible to make correction
using a general image processing method in order to remove external
disturbance factors from data, and obtain a secondary managed
quantity on the basis of plural primary managed quantities. The
general image processing method includes averaging, normalizing and
other methods.
[0087] The second common item is a method of detecting a defect in
the hollow fiber membrane. More specifically, it may be possible to
apply a general image processing technique for inspection of the
defective hollow fiber membrane. For example, it is only necessary
to register, in advance, images 51 to 56 of normal hollow fiber
membranes in FIGS. 3 (a) and 3 (b) as master patterns indicating
normal states in a data buffer of the measurement and inspection
controlling mechanism, and after images 57 to 67 of the defective
hollow fiber membranes as illustrated in FIGS. 4 (a) to 4 (d) are
obtained, and compare them. As a result, in the case of the images
57, 59, 62, and 67 of the defective hollow fiber membranes,
differences in brightness can be detected, and in the case of the
images 58, 60, 61, 63, 64, 65, and 66 of the defective hollow fiber
membranes, differences in plane area can be detected.
Alternatively, as another example, it may be possible to determine
the defective hollow fiber membrane by simply repeating, in the YD
direction, measurement of the outside diameter value which is
obtained by counting the number of pixels in the XD direction of
each image of the hollow fiber membranes and multiplying the
resulting number by the captured-image resolution X .mu.m/pix, and
by detecting a portion whose outside diameter value exceeds a
predetermined tolerable outside diameter value. As' a result, it is
possible to detect the images 58, 60, 61, 63, 64, 65, and 66 of the
defective hollow fiber membranes as abnormality of exceeding the
tolerable outside diameter value. Further, even in the case where
the type of the defective hollow membrane is newly added, if image
characteristics of the image can be distinguished from images of
the normal hollow fiber membranes, it is possible to detect the
defective hollow fiber membrane by modifying the program.
[0088] Here, a more specific description will be given of a method
of obtaining the managed quantities (number, weight, outside
diameter value, and surface area).
[0089] First, as for the number, the number serving as the managed
quantity is only treated as the total amount, and is calculated in
Step 13 in FIG. 5. In particular, in Step 13c, at the start of a
certain turn of the reel, the number is calculated to be "1" for
each of the hollow fiber membranes, and this number is always
maintained during the same turn of the reel (the program is
configured such that Step 13d is ignored in the second turn or
later).
[0090] Next, as for the weight, the weight serving as the managed
quantity is treated as both the total amount and the representative
amount. Note that, during the process of manufacturing the hollow
fiber membrane, a raw material for the hollow fiber membrane is
generally supplied accurately. More specifically, the outside
diameter value may be larger or smaller than the design value due
to variations in formation of the raw material into the shape of
the hollow fiber membrane. In this case, the thickness is small in
the former case, and the thickness is large in the latter case.
However, the amount of the raw material per unit length of the
hollow fiber membrane is constant. Thus, the weight W (unit: mg) of
one hollow fiber membrane contained in the hollow fiber membrane
bundle 13 can be accurately calculated by Equation 1 on the basis
of the weight Wm (unit: mg/mm) of the raw material used per unit
length, and the length L mm of the hollow fiber membrane bundle
13.
W=Wm.times.L Equation 1
[0091] Next, as for the outside diameter, the outside diameter R
.mu.m is calculated using Equation 2 described below on the basis
of the number Xn pix of pixels in the XD direction of an image of
the hollow fiber membrane and the captured-image resolution X
.mu.m/pix in the XD direction, within the minimum unit of
measurement (=area of one pixel in the YD direction) in the
direction in which the hollow fiber membrane is conveyed.
R=X.times.Xn Equation 2
[0092] The outside diameter R dam obtained through Equation 2
described above and serving as the managed quantity is obtained in
Step 13c or Step 23d in the process flow. Naturally, plural outside
diameters R .mu.m can be obtained from one image, and can be
obtained also for each turn of the reel.
[0093] Next, as for the surface area, the present invention assumes
that the surface area is obtained by adding up, in the minimum unit
of measurement, the circumference of a hollow fiber membrane in the
direction in which the hollow fiber membrane is conveyed. Thus, in
the minimum unit of measurement, by using the general formula for
substantially obtaining the circumference, the surface area S
.mu.m.sup.2 is calculated using Equation 3 described below on the
basis of the outside diameter R .mu.m and pi .pi..
S=.pi..times.R Equation 3
[0094] The surface area S .mu.m.sup.2 obtained through Equation 3
described above and serving as the managed quantity is obtained in
Step 13c or Step 23d in the process flow as the circumference in
the minimum unit of measurement. Naturally, plural surface areas S
.mu.m.sup.2 can be obtained from one image, and can be obtained
also for each turn of the reel. Further, the value obtained by
adding up information in the conveying direction has a meaning of
the surface area.
[0095] In the present invention, by using the methods as described
above, the predetermined managed quantities (number, weight,
outside diameter value, and surface area) are obtained in
accordance with the manufacturing conditions or conditions for
quality management, and the manufacturing processes are
automatically controlled on the basis of the total amount (=flow in
FIG. 5), or the representative amounts (=flow in FIG. 6).
[0096] It should be noted that, in the description above, an
example is given in which a general-purpose digital-camera-type
image inspection system is used for the measuring and inspecting
head 20 and the measurement and inspection controlling mechanism
21. However, any device or unit may be used, provided that similar
effects can be obtained with the device or unit. In particular, in
order to optimize specifications of a device, it is preferable to
select, according to manufacturing ability of the manufacturing
processes, each unit that realizes the measuring and inspecting
head 20 and the measurement and inspection controlling mechanism
21, and uniquely build up a system.
Embodiment 2
[0097] The second embodiment of the manufacturing device for a
bundle product according to the present invention includes the
inspecting unit, the cutting and collecting unit, and the
collection-amount adjusting unit. FIGS. 7(a) and 7(b) illustrate
the second embodiment. As in the first embodiment, the inspecting
unit is formed by the measuring and inspecting head 20, and the
measurement and inspection controlling mechanism 21. Further, as
will be described later, the collection-amount adjusting unit is
formed by a cut and collection controlling mechanism 32, and
cutting and collecting means for collecting a thread while cutting
it into a certain length is configured as the cutting and
collecting unit.
[0098] As illustrated in FIGS. 7(a) and 7(b), it may be possible to
use, as the collecting means, the cutting and collecting device in
place of the winding and collecting device in the first embodiment.
The united-thread hollow fiber membrane 11 is cut by the cutter 31
so as to have a predetermined length, and is collected on a
collection tray 28 of a cutting and collecting device 27, and a
united-thread hollow fiber membrane bundle 12' is obtained (as
described above, this is applicable not only to the united-thread
hollow fiber membrane 11 but also to a single thread 10 of a hollow
fiber membrane). The united-thread hollow fiber membrane 11, when
it is cut, is fixed with a clip 29. As illustrated in FIG. 7(b),
clips 291 to 296 circulate on a clip rail 30 with specific
intervals being given therebetween at the speed same as that of the
united-thread hollow fiber membrane 11, hold the united-thread
hollow fiber membrane 11 at a position of the clip 292, and can
move while maintaining this state. As a result, as illustrated in
FIG. 7(b), the united-thread hollow fiber membrane 11 is cut with
the cutter 31 at a time when the united-thread hollow fiber
membrane 11 is held with the three clips 291, 292 and 296.
Immediately after this, the clips 291 and 296 release it, so that
the united-thread hollow fiber membrane bundle 11 is collected on
the collection tray 28. However, the clip 292 continues moving
while keeping holding the united-thread hollow fiber membrane 11.
By repeating these operations, the united-thread hollow fiber
membrane bundles 12' are continuously collected.
[0099] Here, the cut and collection controlling mechanism 32
controls the number of cuts with the cutter 31, in addition to
starting and stopping of operation of the cutting and collecting
device 27, the speed at which the clips move, cutting operations,
and the like. The number of cuts is controlled so that a
predetermined amount of the united-thread hollow fiber membrane
bundle 12' can be obtained. After the predetermined amount is
obtained, the cut and collection controlling mechanism 32 performs
completion operations such as stopping cutting and clip, or
replacing the collection tray 28 with an empty collection tray
which is not illustrated.
[0100] Furthermore, as in embodiment 1, also in embodiment 2, the
measurement and inspection controlling mechanism 21 and the cut and
collection controlling mechanism 32 are configured so that
information can be communicated between them.
[0101] After the predetermined amount of the united-thread hollow
fiber membrane bundles 12' is collected on the collection tray 28,
the united-thread hollow fiber membrane bundle 12' is bound into a
bundle at one end portion thereof with a binding unit which is not
illustrated, is hung with a crane, and is carried out toward the
removing step. Thus, in the case where cutting and collecting are
employed as the collecting means, a step of cutting the hollow
fiber membrane bundle is not required in the cutting step.
[0102] It should be noted that configurations other than those
described above may be similar to those of embodiment 1.
Embodiment 3
[0103] The third embodiment of the manufacturing device for a
bundle product according to the present invention includes the
inspecting unit, a turn-around collecting unit, the cutting unit,
and the collection-amount adjusting unit. FIGS. 8(a) and 8(b)
illustrate the third embodiment. As in the first embodiment, the
inspecting unit is formed by the measuring and inspecting head 20,
and the measurement and inspection controlling mechanism 21.
Further, as will be described later, the collection-amount
adjusting unit is formed by a turn-around collection controlling
mechanism 36. As the turn-around collecting unit, turn-around
collecting means for collecting a thread while turning around the
thread at a certain length is configured.
[0104] As illustrated in FIGS. 8 (a) and 8 (b), it may be possible
to use, as the collecting means, the turn-around collecting device
in place of the winding and collecting device in the first
embodiment. The united-thread hollow fiber membrane 11 is collected
with a turn-around gear 34, which rotates, while being turned
around at a predetermined length with a moving guide 35, and a
united-thread hollow fiber membrane bundle 12'' is obtained (as
described above, this is applicable not only to the united-thread
hollow fiber membrane 11 but also to a single thread 10 of a hollow
fiber membrane). As illustrated in FIG. 8(b) the turn-around
collecting device 33 continuously collects the united-thread hollow
fiber membrane 11 as the united-thread hollow fiber membrane bundle
12'' in a manner such that the moving guide 35 swings the
united-thread hollow fiber membrane 11 to positions 351, 352, and
353 with a fulcrum united-thread guide 251 being a fulcrum, and the
united-thread hollow fiber membrane 11 is looped around a
predetermined tooth of turn-around gears 341 and 342 that rotate in
synchronization with the moving guide 35.
[0105] Here, the turn-around collection controlling mechanism 36
controls the number of turns of the turn-around gear 34, in
addition to starting and stopping of operation of the turn-around
collecting device 33, the speed at which the moving guide moves,
the rotational speed of the turn-around gear, and the like. After
the predetermined amount is obtained, the turn-around collection
controlling mechanism 36 performs completion operations, such as
stopping the turn-around operation and gear-rotating operation, or
replacing the turn-around gear 34 with an empty turn-around gear
which is not illustrated.
[0106] Further, also in embodiment 3, as in embodiment 1 and
embodiment 2, the measurement and inspection controlling mechanism
21 and the turn-around collection controlling mechanism 36 are
configured so that information can be communicated between
them.
[0107] After the predetermined amount of the united-thread hollow
fiber membrane bundles 12'' is collected on the turn-around gear
34, the united-thread hollow fiber membrane bundle 12'' is bound at
one end portion thereof with a binding unit, not illustrated, is
cut at both ends thereof with a cutting tool, not illustrated, is
hung with a crane in this state, and is carried out toward the
removing step.
[0108] It should be noted that configurations other than those
described above may be similar to those of embodiment 1.
Embodiment 4
[0109] The fourth embodiment of the manufacturing device for a
bundle product according to the present invention includes the
inspecting unit, the marker unit, the winding and collecting unit,
and the collection-amount adjusting unit. FIGS. 9(a) and 9(b)
illustrate the fourth embodiment. The inspecting unit, the winding
and collecting unit, and the collection-amount adjusting unit are
configured in a manner similar to that of the first embodiment.
Furthermore, as will be described later, the marker unit includes
at least a marker head 70, and a marker controlling mechanism
71.
[0110] As illustrated in FIGS. 9(a) and 9(b), it is preferable that
the marker head 70 that can apply marking to the single thread 10
of the hollow fiber is provided on the downstream side of the
measuring and inspecting head 20 and on the upstream side of the
winding and collecting device 22. The marker head 70 is controlled
by the marker controlling mechanism 71 configured in a manner that
can communicate with the measurement and inspection controlling
mechanism 21, and applies marking to a single thread 10 of a hollow
fiber membrane determined to be defective by the measurement and
inspection controlling mechanism 21. With the defective fiber
having marking applied thereto, preferably, the operation of
removing the defective fiber in the removing step, which is mainly
performed manually, can be efficiently performed. As for an
instruction of applying the marking, it is only necessary to use
the removing flag in Step 13f and Step 23h illustrated in FIG. 5
and FIG. 6. Note that, although the marking may be applied to a
position in the vicinity of the defect, it is more preferable to
apply the marking to the position substantially the same as the
position in terms of length in the longitudinal direction of the
bundle after the hollow fiber membrane bundle 13 is obtained. This
is because, with this configuration, it is only necessary for the
worker to check only a predetermined position in the longitudinal
direction of the hollow fiber membrane bundle 13, and remove only
the defective fiber from the hollow fiber membrane bundle 13 if the
worker finds the marking. Naturally, in the present invention, the
amount of collection in the collecting step is controlled so that
the managed quantities exceed the standard values after the
defective fiber containing the defective portion is removed.
[0111] It should be noted that configurations other than those
described above may be similar to those of embodiment 1.
Furthermore, also in the collecting steps of embodiments 2 and 3,
it may be possible to apply the marking as in this embodiment.
EXAMPLES
Example 1
[0112] With the configurations illustrated in FIGS. 1(a) and 1(b)
and FIGS. 2 (a) to 2(c), hollow fiber membrane bundles were
manufactured. In other words, a rotational unit was used as the
collecting unit. Furthermore, the number of single threads united
and wound was three. As for the managed quantity for quality of the
hollow fiber membrane bundle, the surface area was used to manage
the total amount. Furthermore, a reel having a circumference of 1.4
m was used. Note that the inspecting unit was formed by a
commercially available LED lamp, a digital line sensor camera, a
lens for general-purpose cameras, an image capturing board, a
signal processing board, a general-purpose PC, and self-made system
controlling software using C language. The collection-amount
adjusting unit is formed by a commercially available programmable
controller and self-made controlling software using the ladder
language.
[0113] As for conditions for manufacturing the hollow fiber
membranes, a design value of the outside diameter was set to 1425
.mu.m. More specifically, a design value of the circumference was
0.0044745 m, and a design value of the surface area per hollow
fiber membrane of one turn of the reel was 0.0062643 m.sup.2. Note
that this hollow fiber membrane bundle was finally incorporated
into a module for water treatment, which is a final product. In
order to ensure the performance of the module, it is necessary for
this hollow fiber membrane bundle to have a standard value of 4.02
m.sup.2 for the total surface area. If the hollow fiber membrane
bundle is formed by 642 single threads, the total surface area is
4.0216806 m.sup.2 on the assumption that the hollow fiber membrane
is manufactured ideally in accordance with the design values, and
satisfies the standard value. In other words, it is only necessary
to rotate the reel by 214 turns under the conditions for
manufacturing three united threads. Note that the managed width in
connection with the abnormality of the outside diameter of a single
hollow fiber membrane is set in the range of 1350 to 1500 .mu.m in
order to avoid causing inconveniences to customers during the time
when the module is being used, which has been already
described.
[0114] Under the conditions as described above, the hollow fiber
membrane bundle was manufactured. As a result, depending on the
manufacturing states of a certain lot, the outside diameter of the
hollow fiber membrane tended to be smaller than the design value (a
median value was approximately 1370 .mu.m), and at the time when
the reel rotated 214 turns, the total surface area was 3.87
m.sup.2, and had not reached the standard value of 4.02 m.sup.2.
Thus, the collection-amount adjusting unit continued to perform
collection while controlling the collecting unit. Then, at the time
when the reel rotated 223 turns, the total surface are of the
hollow fiber membrane reached 4.03 m.sup.2, and satisfied the
standard value (note that the number of hollow fiber membranes was
669). On the contrary, in the manufacturing state of another lot,
the outside diameter of the hollow fiber membrane tended to be
larger than the design value (a median value was approximately 1488
.mu.m), and at the time when the reel rotated 205 turns, the total
surface area of the hollow fiber membrane was 4.023 m.sup.2, which
satisfied the standard value (note that the number of the hollow
fiber membranes was 615).
[0115] Furthermore, in the manufacturing state of another lot, the
hollow fiber membrane was manufactured with the outside diameter of
the hollow fiber being almost the design value (a median value was
approximately 1422 .mu.m). However, immediately after the reel
rotated 186 turns, one of the three single threads was cut. Thus,
after that, only two single threads were collected. At the time
when the reel rotated 229 turns, the total surface area of the
hollow fiber membrane was 4.026 m.sup.2, which satisfied the
standard value (note that the number of the hollow fiber membranes
was 644).
[0116] The hollow fiber membranes manufactured in the
above-described cases were each assembled in a module, and final
inspection before shipping of the modules was performed on these
modules. As a result, these modules exhibited sufficient filtration
performance.
Example 2
[0117] For a certain type of the hollow fiber membrane bundle, it
is known that the manufacturing state is sufficiently stable, and
the initial state continues. Thus, the surface area serving as the
managed quantity was managed using representative amounts.
Conditions for calculating the representative amount were set such
that the reel rotated up to 3 turns; the outside diameter was
measured once for each of three single threads; and the number of
rotations of the reel was obtained on the basis of the average
value of nine pieces of outside diameter data. Under these
conditions, manufacturing was performed (note that conditions other
than those described above were similar to those in Example 1).
[0118] As a result, the following outside diameter data were
obtained: for the first single thread, 1452 .mu.m (first turn),
1454 .mu.m (second turn), and 1452 .mu.m (third turn); for the
second single thread, 1451 .mu.m (first turn), 1450 .mu.m (second
turn), and 1452 .mu.m (third turn); and for the third single
thread, 1454 .mu.m (first turn), 1455 .mu.m (second turn), and 1453
.mu.m (third turn). Further, by averaging these data, the average
outside diameter of 1452.56 .mu.m was obtained. On the basis of
this outside diameter, in order to satisfy the standard value of
4.02 m.sup.2 for the surface area, the hollow fiber membrane bundle
was configured by setting the number of rotations of the reel to
210 turns, and setting the number of single threads to 630. This
hollow fiber membrane bundle was assembled in a module, and final
inspection before the shipment of the module was performed on the
module. As a result, the module exhibited sufficient filtration
performance.
[0119] Furthermore, in this Example, the managed quantity did not
have to be always monitored. Thus, it was possible to significantly
reduce the amount of processing load that the general-purpose PC
used as the inspecting unit has to carry. This makes it possible
to, for example, view the past inspection information, organize
data, create documents, and duplicate various electronic data to an
external medium while manufacturing the hollow fiber membrane
bundle. As a result, it is possible to improve efficiency of the
entire operations.
Example 3
[0120] A hollow fiber membrane bundle was manufactured using the
configuration in FIGS. 9(a) and 9(b) in place of the configuration
illustrated in FIGS. 1(a) and 1(b). In the configuration in FIGS. 9
(a) and 9(b), a marker was provided in addition to the
configuration in FIGS. 1(a) and 1(b). This marker applied a marking
to a defective fiber on the basis of inspection results with a
measuring and inspecting unit (note that conditions other than
those described above were similar to those in Example 2). Note
that, for the marker, a commercially available laser marker (made
by Keyence Corporation) was used.
[0121] As a result, during the time when the hollow fiber membrane
bundle was manufactured, the measuring and inspecting unit detected
6 defective hollow fiber membranes (scratch), 17 defective hollow
fiber membranes (foreign substance), and 8 defective hollow fiber
membranes (swelling), each of which is to be contained in the
hollow fiber membrane bundle to be finally obtained in the cutting
step. On the basis of these results, the collection-amount
adjusting unit increased the number of rotations of the reel by 11
turns to 221 turns from 210 turns, which is the number of rotations
in the case where no defective hollow fiber membrane exists.
[0122] Further, at the time when the hollow fiber membrane bundle
was obtained in the cutting step, the marker applied markings to
these defective hollow fiber membranes through firing with emission
of laser from a distance in a range of 100 to 250 mm by setting the
position of the binding unit to the reference.
[0123] At the time when manufacturing was completed, this hollow
fiber membrane bundle contained 663 single threads. However, an
operator checked the markings in the removing step, and removed 31
defective hollow fiber membranes, which were determined to be the
defective by the measuring and inspecting unit. Finally, the number
of the hollow fiber membranes was 632. This hollow fiber membrane
bundle was assembled in a module, and final inspection before the
shipment of the module was performed on the module. As a result,
the module exhibited sufficient filtration performance.
Furthermore, since the defective hollow fiber membranes were
accurately removed, no abnormality was found in the module also
during the time when the module was used by a customer.
Example 4
[0124] A hollow fiber membrane bundle was manufactured using the
configuration illustrated in FIGS. 7(a) and 7(b) in place of the
configuration in FIGS. 1(a) and 1(b). More specifically, the
cutting and collecting unit was used for the collecting unit, and
the cutting step included only an operation of hanging the hollow
fiber membrane bundle, while removing the cutting operation.
Furthermore, the outside diameter was employed as the managed
quantity for quality of the hollow fiber membrane bundle. (Note
that conditions other than those described above were similar to
those in Example 1.)
[0125] As described in Example 1, the design value of the outside
diameter of the hollow fiber membrane was 1425 .mu.m. In order to
ensure the performance of the module having the hollow fiber
membrane bundle finally assembled therein, the standard value of
the total outside diameter of this hollow fiber membrane bundle is
1.28 m. If the hollow fiber membrane bundle is formed by 642
singles threads, the total outside diameter was 1.28079 m on the
assumption that the hollow fiber membrane was manufactured ideally
in accordance with the design values, and it is possible to satisfy
the standard value. In other words, it is only necessary to rotate
the reel by 214 turns under the manufacturing conditions for three
united threads.
[0126] Under these conditions, the hollow fiber membrane bundle was
manufactured. As a result, depending on the manufacturing states of
a certain lot, the outside diameter of the hollow fiber member
tended to be larger than the design value (a median value was
approximately 1467 .mu.m), and at the time when the reel rotated
208 turns, the total outside diameter of the hollow fiber membrane
was 1.282 m, and satisfied the standard value (the number of the
hollow fiber membranes was 624). This hollow fiber membrane bundle
was assembled in a module, and final inspection before the shipment
of the module was performed on the module. As a result, the module
exhibited sufficient filtration performance.
[0127] The hollow fiber membranes were collected and cut at the
same time, which realized reduction in time required for the entire
processes for manufacturing the hollow fiber membrane bundle.
Comparative Example
[0128] On the other hand, in a manufacturing state similar to that
in Example 1, a hollow fiber membrane bundle was manufactured
without adjusting the amount of collection of the hollow fiber
membranes and the effect of the present invention was confirmed. As
a result, regardless of the manufacturing states of the hollow
fiber membrane, the reel stopped rotating at 214 turns on the basis
of the design value, and hence, in the case where the outside
diameter of the hollow fiber membrane was smaller than the design
value, the total surface area of the hollow fiber membrane bundle
did not satisfy the standard value. Thus, the module did not
sufficiently exhibit the filtration performance in the final
inspection before the module is shipped, and was discarded as a
defective product. On the other hand, in the case where the outside
diameter of the hollow fiber membrane is larger than the design
value, the total surface area of the hollow fiber membrane bundle
satisfied the standard value, while the volume of the hollow fiber
membrane bundle was larger than necessary, and the hollow fiber
membrane bundle was not able to be inserted into a module. Thus,
single threads had to be removed from the hollow fiber membrane
bundle until the hollow fiber membrane bundle was able to be
inserted into the module.
[0129] Further, in the case where cutting of threads occurred
during manufacturing, the number of hollow fiber membranes that are
short of the design value had to be counted after collection was
completed, and the necessary number of hollow fiber membranes had
to be added, which was the troublesome labor and time.
REFERENCE SIGNS LIST
[0130] 10 Single thread of hollow fiber membrane [0131] 11
United-thread hollow fiber membrane having plural single threads
united therein [0132] 12 Collected united-thread hollow fiber
membrane bundle [0133] 12' United-thread hollow fiber membrane
bundle collected after cutting [0134] 12'' United-thread hollow
fiber membrane bundle collected through turning-around [0135] 13
Hollow fiber membrane bundle [0136] 20 Measuring and inspecting
head [0137] 21 Measurement and inspection controlling mechanism
[0138] 22 Winding and collecting device [0139] 23 Reel [0140] 231
First reel position [0141] 232 Second reel position [0142] 233
Third reel position [0143] 24 Winding and collection controlling
mechanism [0144] 25 United-thread guide [0145] 251 Fulcrum
united-thread guide [0146] 26 Roll [0147] 27 Cutting and collecting
device [0148] 28 Collection tray [0149] 29 Clip [0150] 291, 292,
293, 294, 295, 296 Clip (individual) [0151] 30 Clip rail [0152] 31
Cutter [0153] 32 Cut and collection controlling mechanism [0154] 33
Turn-around collecting device [0155] 34, 341, 342 Turn-around gear
[0156] 35 Moving guide [0157] 351, 352, 353 Positions of moving
guide [0158] 36 Turn-around collection controlling mechanism [0159]
37 Thread path guide [0160] 40 Cutter [0161] 401 Cutter at cutting
position [0162] 41 Binding unit [0163] 42 Hanging rope [0164] 43
Crane rail [0165] 44 Crane [0166] 50 Image [0167] 51, 52, 53, 55
Image of hollow fiber membrane having outside diameter of .beta.
[0168] 54 Image of hollow fiber membrane having outside diameter of
.alpha. [0169] 56 Image of hollow fiber membrane having outside
diameter of .gamma. [0170] 57 Image of defective hollow fiber
membrane (scratch) [0171] 58 Image of defective hollow fiber
membrane (defect) [0172] 59 Image of defective hollow fiber
membrane (foreign substance) [0173] 60 Image of defective hollow
fiber membrane (dent) [0174] 61 Image of defective hollow fiber
membrane (swelling) [0175] 62 Image of defective hollow fiber
membrane (large hole) [0176] 63 Image of defective hollow fiber
membrane (excessively thin; underrunning lower limit value .alpha.)
[0177] 64 Image of defective hollow fiber membrane (excessively
thick; exceeding upper limit value .gamma.) [0178] 65 Image of
defective hollow fiber membrane (crushed) [0179] 66 Image of
defective hollow fiber membrane (twisted) [0180] 67 Image of
defective hollow fiber membrane (clogged) [0181] 68 State where
cutting of thread occurs [0182] 70 Marker head [0183] 71 Marker
controlling mechanism
* * * * *