U.S. patent application number 11/760173 was filed with the patent office on 2008-02-28 for holding sealer and exhaust gas processing device.
This patent application is currently assigned to IBIDEN CO., LTD.. Invention is credited to Junichi SUGINO.
Application Number | 20080047638 11/760173 |
Document ID | / |
Family ID | 38321578 |
Filed Date | 2008-02-28 |
United States Patent
Application |
20080047638 |
Kind Code |
A1 |
SUGINO; Junichi |
February 28, 2008 |
HOLDING SEALER AND EXHAUST GAS PROCESSING DEVICE
Abstract
There is provided a holding sealer comprising a mat base member
including inorganic fibers and a protective sheet provided on a
surface of the mat base member, in which the holding sealer is
formed as a rectangular shape, wherein the protective sheet is
extended in a different direction inside the surface of the
protective sheet, and the protective sheet is placed on the surface
of the mat base member such that a direction showing the maximum
extension of the protective sheet is arranged at an angle except
zero to a long length direction of the holding sealer.
Inventors: |
SUGINO; Junichi; (Ogaki-Shi,
JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
IBIDEN CO., LTD.
Ogaki-Shi
JP
|
Family ID: |
38321578 |
Appl. No.: |
11/760173 |
Filed: |
June 8, 2007 |
Current U.S.
Class: |
150/157 |
Current CPC
Class: |
F01N 3/0211 20130101;
F01N 2350/06 20130101; Y02T 10/12 20130101; Y02T 10/20 20130101;
F01N 3/2853 20130101; F01N 3/2864 20130101 |
Class at
Publication: |
150/157 |
International
Class: |
B65D 65/02 20060101
B65D065/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 24, 2006 |
JP |
2006-228153 |
Claims
1. A holding sealer comprising a mat base member including
inorganic fibers and a protective sheet provided on a surface of
the mat base member, in which the holding sealer is formed as a
rectangular shape, wherein the protective sheet is extended in a
different direction inside the surface of the protective sheet, and
the protective sheet is placed on the surface of the mat base
member such that a direction showing the maximum extension of the
protective sheet is arranged at an angle except zero to a long
length direction of the holding sealer.
2. The holding sealer as claimed in claim 1, wherein the protective
sheet is provided on the surface of the mat base member such that
the direction showing the maximum extension of the protective sheet
is substantially perpendicular to the long length direction of the
holding sealer.
3. The holding sealer as claimed in claim wherein the protective
sheet is made by polypropylene.
4. The holding sealer as claimed in claim 1, wherein the mat base
member includes an inorganic binder and/or an organic binder.
5. An exhaust gas processing device comprising: an exhaust gas
processing body; a holding sealer comprising a mat base member
including inorganic fibers and a protective sheet provided on a
surface of the mat base member, in which the holding sealer is used
such that the holding sealer is wound around the at least part of
an outer circumference surface of the exhaust gas processing body
so as to face the protective sheet outside, wherein the protective
sheet is extended in different a direction inside the surface of
the protective sheet, and the protective sheet is placed on the
surface of the mat base member such that a direction showing the
maximum extension of the protective sheet is arranged at an angle
except zero to a long length direction of the holding sealer; and a
casing housing the exhaust gas processing body and the holding
sealer therein.
6. The exhaust gas processing device as claimed in claim 5, wherein
the exhaust gas processing body is a catalyst carrier or an exhaust
gas filter.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention generally relates to a holding sealer having
a mat base member including inorganic fibers and a protective sheet
placed on a surface of the mat base member, also an exhaust gas
processing device including such a holding sealer.
[0003] 2. Description of the Related Art
[0004] The number of cars has been greatly increasing since the
beginning of this century, and the amount of exhaust gas from car
engines has been increasing amazingly along with the increasing
number of cars. Especially, various materials in the exhaust gas
from diesel engines trigger environmental pollution, so that these
materials are currently seriously influencing the global
environment.
[0005] Under these circumstances, various exhaust gas processing
devices have been suggested, and these have been used practically.
A typical exhaust gas processing device has a casing (for example,
made of metal and the like) on a exhaust pipe connected to an
exhaust gas manifold of the engine, in which casing an exhaust gas
processing body having lots of cells, which are divided by cell
walls, is arranged thereon. Typically, these cells are in a
honeycomb structure; in this case, the exhaust gas processing body
is called a honeycomb structure body. As an example of the exhaust
gas processing body, there are an exhaust gas filter such as a
catalyst carrier and a diesel particulate filter (DPF) and the
like. For example, in the case of DPF, particles are trapped by
cell walls during the exhaust gas passing through the exhaust gas
processing body via each cell based on the above structure; thereby
particles can be removed from the exhaust gas. Structural materials
of the exhaust gas processing body are metals, alloys, ceramics,
etc. As a typical example of the exhaust gas processing body
comprising ceramics, a honeycomb filter made by cordierite is
known. Recently, from the viewpoint of heat resistance, mechanical
strength, chemical stability, etc., a porous silundum sintering
body is used as the exhaust gas processing body.
[0006] Usually, the holding sealer is placed between the above
exhaust gas processing body and the casing. The holding sealer is
used for protecting against breakage due to contact of the exhaust
gas processing body with an inner surface of the casing during
vehicle runs, and for protecting against leakage of the exhaust gas
from a gap between the casing and the exhaust gas processing body.
Also, the holding sealer plays an important role for preventing the
exhaust gas processing body from falling off due to the exhaust
pressure of the exhaust gas. Moreover, the exhaust gas processing
body needs to keep high temperature for stabilizing the reaction,
and also the holding sealer needs to be heat resistant. As a
structural member satisfying these requirements, there is a sheet
member including inorganic fibers such as alumina system fiber,
etc.
[0007] The holding sealer is wound around at least a portion of an
outer surface except an open surface of the exhaust gas processing
body, for example, both edges of the holding sealer are engaged,
and the holding sealer is used by fixing as one body with the
exhaust gas processing body by means of taping. Then, the one whole
body is assembled into the exhaust gas processing device by being
pressed into the casing.
[0008] Here, when the holding sealer is wound around the outer
surface of the exhaust gas processing body, some tension occurs in
the holding sealer along the winding direction. This tension occurs
remarkably on a surface which is the outside of the holding sealer
due to the different circumference lengths (difference between an
outer circumference length and an inner circumference length).
Because of this, when the strength of the holding sealer is not
enough, cracks may occur on the outer surface of the holding sealer
especially at the time of winding the holding sealer around the
exhaust gas processing body. Leakage of the unprocessed exhaust gas
occurs because such cracks decrease the sealing ability of the
holding sealer.
[0009] Because of this, in order to prevent the leakage of
non-processed exhaust gas due to the occurrence of such cracks, for
example, it is proposed to provide a protective sheet having
flexibility on the surface of the contacting side (i.e., on the
outer circumference side) with an inner wall of the casing of the
holding sealer (For example, see Patent Document 1). The following
method is disclosed in the above patent document. In this method,
the occurrence of cracks on the outer circumference side of the
holding sealer is restricted due to the protective sheet having
flexibility and being provided on the holding sealer, thereby the
leakage of non-processed exhaust gas can be restricted.
[0010] Patent Document 1: JP 2001-521847
SUMMARY OF THE INVENTION
[0011] In order to achieve the above-mentioned object, there is
provided according to one aspect of the present invention a holding
sealer comprising a mat base member including inorganic fibers and
a protective sheet provided on a surface of the mat base member, in
which the holding sealer is formed in a rectangular shape,
[0012] wherein the protective sheet is extended in a different
direction inside the surface of the protective sheet, and
[0013] the protective sheet is placed on the surface of the mat
base member such that a direction showing the maximum extension of
the protective sheet is arranged at an angle except zero to the
long length direction of the holding sealer.
[0014] Additionally, in the holding sealer according to the present
invention, it is preferable that the protective sheet be provided
on the surface of the mat base member such that the direction
showing the maximum extension of the protective sheet is
substantially perpendicular to the long length direction of the
holding sealer.
[0015] Additionally, in the holding sealer according to the present
invention, the protective sheet may be made by polypropylene.
[0016] Additionally, in the holding sealer according to the present
invention, the mat base member may include an inorganic binder
and/or an organic binder.
[0017] In order to achieve the above-mentioned object, there is
provided according to another aspect of the present invention, an
exhaust gas processing device comprising:
[0018] an exhaust gas processing body;
[0019] a holding sealer comprising a mat base member including
inorganic fibers and a protective sheet provided on a surface of
the mat base member, in which the holding sealer is used such that
the holding sealer is wound around at least a part of an outer
circumference surface of the exhaust gas processing body so as to
face the protective sheet outside,
[0020] wherein the protective sheet is extended in a different
direction inside the surface of the protective sheet, and
[0021] the protective sheet is placed on the surface of the mat
base member such that a direction showing the maximum extension of
the protective sheet is arranged at an angle except zero to a long
length direction of the holding sealer; and
[0022] a casing housing the exhaust gas processing body and the
holding sealer therein.
[0023] Additionally, in the exhaust gas processing device according
to the present invention, the exhaust gas processing body may be a
catalyst carrier or an exhaust gas filter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Other objects, features and advantages of the present
invention will become more apparent from the following detailed
description when read in conjunction with the accompanying
drawings, in which:
[0025] FIG. 1 is an example of a structure of the holding sealer of
the present invention;
[0026] FIG. 2 is a schematic view showing a situation where the
holding sealer and the exhaust gas processing body of the present
invention are incorporated into the casing;
[0027] FIG. 3 is a perspective view and its sectional view taken at
A-A showing schematically a situation that a coated exhaust gas
processing body having a conventional holding sealer is press-fit
into the casing;
[0028] FIG. 4 is a perspective view and its sectional view taken at
B-B showing schematically a situation where a coated exhaust gas
processing body having the holding sealer of the present invention
is press-fit into the casing;
[0029] FIG. 5 is a schematic view showing a method of placing a
coated exhaust gas processing body into the casing by press-fit
means; and
[0030] FIG. 6 is a view showing one structural example of the
exhaust gas processing device of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] Next, a description is given, with reference to the
accompanying drawings, of an embodiment according to the present
invention. In the below description, the mat base member means a
mat member including inorganic fiber which comprises a basic part
of the holding sealer. The protective sheet means a sheet member
which is placed to cover at least one surface of the mat base
member. Therefore, the holding sealer of the present invention
comprises the mat base member and the protective sheet. Also, the
material of the sheet member is not limited; all sheet members
showing an extension in a different direction inside the surface of
the sheet including paper, plastic, non-woven fabric and silk paper
can be included for the sheet member.
[0032] In FIG. 1, an example of a structure of the holding sealer
of the present invention is shown. Also, an exploded view of the
exhaust gas processing device including the holding sealer of the
present invention is shown in FIG. 2.
[0033] As shown in FIG. 1, the holding sealer according to the
present invention has a long length (parallel length to the X
direction) and a short length (parallel length to the Y direction),
and it is formed substantially as a rectangular shape. A fitting
salient 50 and a fitting reentrant 60 are provided respectively on
the short length 70 and 71. Also, a couple of salient parts 61 are
formed at positions that are next to the fitting reentrant 60 on
the short length 71. However, the short length 70 or 71 of the
holding sealer of the present invention is not limited to the shape
of FIG. 1, but a shape can be used of a length that does not have
fitting parts as shown in FIG. 1 at all or each short length has
plural respective fitting salients 50 and fitting reentrants 60,
and the like, for example. Also, in the specification of the
present invention, "formed substantially as a rectangular shape"
means a general idea including a rectangular shape having a pair of
fitting salients 50 and a fitting reentrant 60 on a short length as
shown in FIG. 1. Also, "formed substantially as a rectangular
shape" includes a shape in which an angle between a long length and
a short length is other than 90 degrees (for example, a shape
having a curvature).
[0034] This holding sealer 24 is used such that the long length
direction is the winding direction (X direction). When the holding
sealer 24 is wound around the exhaust gas processing body 20 like
the catalyst carrier, the fitting salient 50 and the fitting
reentrant 60 are fitted together and the holding sealer 24 is fixed
on the exhaust gas processing body 20 as shown in FIG. 2. Then, the
exhaust gas processing body 20 which the holding sealer 24 is wound
around (herein below, it is called the coated exhaust gas
processing body) is installed into the cylindrical casing 12 made
of metal and the like by the press-fit means.
[0035] Here, in an embodiment according to the present invention,
the holding sealer 24 is composed of the mat base member 26 as the
base of the holding sealer and the protective sheet 28 laminated on
the mat base member 26. The protective sheet 28 is placed in order
to restrict the occurrence of cracks which might take place on the
outer surface of the holding sealer when the holding sealer 24 is
wound around the exhaust gas processing body 20 as explained in
Description of the Related Art. Thus, the holding sealer 24 is
wound around the exhaust gas processing body 20 such that the
protective sheet 28 faces outside when the holding sealer 24 is
wound around the exhaust gas processing body 20. In the example of
FIG. 1, the protective sheet 28 is placed such that a direction 30
which shows the maximum extension becomes a short direction (Y
direction) of the holding sealer 24, that is, the direction 30
becomes a direction which is substantially perpendicular to the
winding direction.
[0036] Effects obtained from the holding sealer 24 of an embodiment
according to the present invention will be explained below in
comparison to the holding sealer which has the conventional
protective sheet.
[0037] FIG. 3 and FIG. 4 show schematic perspective views of the
coated exhaust gas processing bodies 440 and 44, in which the
coated exhaust gas processing bodies 440 and 44 including holding
sealer 240 having the conventional protective sheet and the holding
sealer 24 having the protective sheet of the present invention
respectively are installed in the casing 12 by the press-fit means.
Also, below FIG. 3 and FIG. 4, A-A sectional view (FIG. 3) and B-B
sectional view (FIG. 4) which are through the fitting part 50 (60)
of respective FIG. 3 and FIG. 4 are shown. In these figures, the
casing 12 is omitted for simplification.
[0038] In general, the protective sheet 28 has a different
directional ability inside the surface concerning the extension. In
the usual case, the protective sheet 28 is placed such that the
direction 30 which shows the maximum extension is substantially
parallel to the long length direction (X direction of FIG. 1) of
the holding sealer 240. This is because of the easy handling of the
holding sealer 240 at the time of winding around. In this case, the
direction 30 which shows the maximum extension of the protective
sheet 28 corresponds to a circumference direction of the coated
exhaust gas processing body 440 as shown in FIG. 3. When the coated
exhaust gas processing body 440 is press-fit into the casing 12 in
this circumstance, it is highly likely that partial positional
difference and/or the crowded wrinkle 67 will occur on the holding
sealer 240 due to a frictional force to be received by the inner
wall of the casing at the time of the press-fitting. Especially,
such partial positional difference and/or the crowded wrinkle 67
occurs on the fitting parts, so that the fitting salient 50 and the
fitting reentrant 60 are not matched and a gap 65 is formed between
the fitting salient 50 and the salient part 61 which is next to the
fitting salient 50 in one direction (or both directions). This kind
of gap is a cause of the leakage of the non-processed exhaust
gas.
[0039] On the contrary, an embodiment according to the present
invention has a characteristic that the protective sheet 28 is
placed such that the direction 30 which shows the maximum extension
is substantially non-parallel to the long length direction (X
direction of FIG. 1) of the holding sealer 240 (for example, it is
substantially perpendicular, as shown in FIG. 4). In this case, the
partial positional difference and/or the crowded wrinkle 67 on the
holding sealer 24 hardly take place due to the above frictional
force to be received by the inner wall of the casing. It is
possible for the protective sheet 28 of the present invention to be
extended along the press-fitting direction, thereby a deformation
of the whole holding sealer 24 is not restricted. Especially, as
shown in FIG. 4, when the direction 30 which shows the maximum
extension of the protective sheet 28 is placed so as to become
substantially the short length direction of the holding sealer 24,
this direction 30 is substantially parallel to the press-fitting
direction of the coated exhaust gas processing body 44. Thereby,
the direction 30 has the maximum extension ability to the
press-fitting direction of the protective sheet 28, and an
extremely good deformation moderation effect is provided.
Therefore, the partial positional difference and/or the crowded
wrinkle 67 and the gap 65 of the fitting parts as shown in FIG. 3
hardly form on the holding sealer 24 of the present invention, even
though the coated exhaust gas processing body 44 is press-fit into
the casing 12.
[0040] Thus, not only the occurrence of cracks on the outer
circumference side of the holding sealer of an embodiment according
to the present invention when the holding sealer 24 is wound around
the exhaust gas processing body 20 by the protective sheet is
restricted, but also the occurrence of partial positional
difference and/or the crowded wrinkle and the gap of the fitting
parts on the holding sealer 24 is restricted. Therefore, it is
possible to restrict advantageously the leakage of the
non-processed exhaust gas due to both effects for the exhaust gas
processing device using the holding sealer of the present
invention.
[0041] Also, in an embodiment according to the present invention,
materials of the protective sheet 28 are not limited, but it is
preferable that material be a plastic having flexibility like
polypropylene, for example.
[0042] The thickness of the protective sheet 28 is not limited to a
certain thickness. However, when the protective sheet is too thin,
the above deformation moderation effect weakens. On the other hand,
when the protective sheet is too thick, the handling of the
protective sheet is hard. Thereby, it is preferable that the
thickness of the protective sheet be between about 1 .mu.m and
about 1 mm or less. Also, the ratio of the thickness of the
protective sheet 28 and the thickness of the mat base member 26 as
a base is not limited to a certain ratio, but it is preferable that
the ratio be in the range between about 1:10 and about 1:1000. It
is more preferable that the ratio be in the range between about
1:50 and about 1:200.
[0043] Also, an adhesion method between the protective sheet 28 and
the mat base member 26 is not limited to a certain method.
Especially, it is preferable that both be adhesive via an adhesive
including organic binders and the like.
[0044] This holding sealer 24 is wound around the outer
circumference surface of the exhaust gas processing body 20 such
that the protective sheet 28 faces outside (that is, the protective
sheet 28 faces the casing 12) as described in the above, and ends
70 and 71 of the holding sealer are fitted together and fixed;
thereby the holding sealer is used. After this, the exhaust gas
processing body 20 around which the holding sealer 24 is wound is
forced into the casing 12 by the press-fit means, and thereby the
exhaust gas processing device is constructed.
[0045] The press-fit means is a method of constructing the exhaust
gas processing device 10 to place the coated exhaust gas processing
body 44 at the predetermined position by pushing the coated exhaust
gas processing body 44 into the casing 12 from one of the opening
sides of the casing 12. In order to facilitate the insertion into
the casing 12 of the coated exhaust gas processing body 44, as
shown in FIG. 5, there is a case that a press-fit tool 15, in which
the inner diameter is gradually decreased from one end to the other
end and the minimum inner diameter is adjusted to be almost the
same as the inner diameter of the casing 12, may be used. In this
case, the coated exhaust gas processing body 44 is inserted from a
wide inner diameter side of the press-fit tool 15, and placed into
the casing 12 through the minimum inner diameter side.
[0046] One structural example of the exhaust gas processing device
10 which is constructed in such a way is shown in FIG. 6. In the
example of FIG. 6, the exhaust gas processing body 20 is a catalyst
carrier having many through-holes in a parallel direction of the
gas flow. For example, the catalyst carrier is composed of
honeycomb-shaped porous silundum and the like. Also, the exhaust
gas processing device 10 of the present embodiment is not limited
to such a structure. For example, the exhaust gas processing body
20 can be DPF, in which ends of through-holes are sealed in a
checkered design. In such an exhaust gas processing device, the
exhaust gas which is introduced into the device is not passed
through the holding sealer nor discharged without processing
because of the effect of the above holding sealer (more precisely,
the protective sheet).
[0047] One example of a manufacturing method of the holding sealer
of the present invention is explained below.
[0048] The mat base member of the holding sealer of the present
invention can be manufactured by a papermaking method. The
papermaking method is also called usual wet processing, and it is a
processing method for manufacturing the holding sealer through each
process of mixing of fibers, stirring, opening of fibers,
slurrying, paper molding and compression drying as in
papermaking.
[0049] First, predetermined quantities of inorganic fiber raw
materials, inorganic binders and organic binders are mixed in
water. Original cotton bulk of mixed fibers of alumina and silica
as inorganic fiber raw materials can be used, for example. However,
inorganic fiber raw materials are not limited to the above
materials; for example, inorganic fiber raw materials may be
composed of only alumina and silica. Alumina sol and silica sol and
the like are used as inorganic binders, for example. Also, latex
and the like are used as organic binders.
[0050] Next, the obtained mixture is stirred like a papermaker, and
open fiber slurry is prepared. Usually, the stirring and opening
fiber process is performed for about 20-about 120 seconds. Then,
the obtained slurry is molded in a desired shape in a molding
machine, and a material mat of the mat base member is obtained by
further dehydration.
[0051] Further, this material mat is compressed with a pressing
machine and the like, then heated and dried at a predetermined
temperature. The compression process is performed such that the
density of the mat base member obtained after finishing of usual
compression becomes about 0.10 g/cm.sup.3-about 0.40 g/cm.sup.3.
The heating and drying process is performed at about 90-about
150.degree. C. for about 5-about 60 minutes such that the material
mat is placed inside a heating processing machine like an oven. The
mat base member is manufactured via this kind of process.
[0052] The obtained mat base member is cut for easy handling, and
is further used for cutting in a predetermined final shape.
[0053] Next, binder is coated on one side surface of the mat base
member which is cut, and the protective sheet having a
predetermined shape (usually, same dimensional shape as well as the
one side surface of the mat base member) is stuck thereon. In this
case, it is preferable for sticking of the protective sheet such
that the direction obtaining the maximum extension be substantially
perpendicular to the long length direction (X direction in FIG. 1)
of the holding sealer after completion. However, the direction
obtaining the maximum extension of the protective sheet is not
limited to the above. The direction obtaining the maximum extension
of the protective sheet may be any direction except the long length
direction of the holding sealer in the case of obtaining the above
effect for the holding sealer.
[0054] The binder is not limited to a certain binder, but the
organic resin is preferable for the binder. It is preferable to use
acrylic resin (ACM), acrylnitryl-butadiene gum (NBR), and
stylene-butadiene gum (SBR) as organic binders. Also, it is
preferable that the amount of organic binder be between 1.0 and
10.0 weight % for the mat base member. If the amount of organic
binder is about 1.0 weight % or more, an adhesive effect of the
protective sheet can be obtained sufficiently. Also, if the amount
of organic binder is about 10.0 weight % or less, the amount of the
organic contents which is discharged at the time of use of the
exhaust gas processing device is not increased.
[0055] In the next step, by the heat compression drying method, the
binder is dried and solidified. Thereby, the protective sheet is
adhered on the mat base member. The drying process is performed
around about 95-about 155.degree. C. If the temperature is about
95.degree. C. or more, the drying time does not take more time and
production efficiency does not decrease. Also, if the drying
temperature is about 155.degree. C. or less in the case of using
organic binders, decomposition of organic binders themselves does
not begin to start and adhesive performance due to organic binders
is not lost.
[0056] Thus, the holding sealer in which the protective sheet
showing the maximum extension in a desired arranging direction is
placed on the surface of the mat base member can be obtained.
Thereby, the exhaust gas processing device in which the leakage of
the non-processed exhaust gas is advantageously restrained can be
obtained by using the holding sealer according to the present
invention.
[0057] Below, effects of an embodiment according to the present
invention will be explained using examples.
EXAMPLES
[0058] In order to verify effects of the present invention, each
kind of examination was performed using the holding sealer of the
present invention. The holding sealer was manufactured by following
procedures.
[0059] Manufacturing 1 of the Holding Sealer
[0060] Original cotton bulk of alumina fibers 1200 g, organic
binder (latex) 60 g, inorganic binder (alumina sol) 12 g and water
were added, and the mixture was mixed with so that the fiber
density in a material solution became 5 weight %. Then, the
material solution was stirred in a papermaker for 60 seconds. Thus,
the material solution which was stirred and opened fiber was moved
to the molding machine having a dimension of 930 mm.times.515
mm.times.400 mm. Then, the material mat of alumina fibers was
obtained by removing water via a mesh placing on a bottom surface
of the molding machine. In the next, the material mat was
press-dried for 30 minutes at 120.degree. C. and a mat base member
having 14 mm of thickness and 0.19 g/cm.sup.3 density was
obtained.
[0061] About 30 ml of the latex (about 5 wt % to the weight of the
mat base member) was coated on one side surface of the mat base
member, PP (polypropylene) non-woven fabric A (product name: ELTAS,
PO3015, Asahi-Kasei Seni) is provided thereon. The PP non-woven
fabric A is provided on the mat base member such that the direction
having the maximum extension is substantially parallel to the short
length direction of the holding sealer sample after completion.
Next, the latex was dried and rigidified at temperature of
120.degree. C. and pressure of 30 kPa, then the mat base member and
the PP non-woven fabric A were adhered. This mat base member was
cut in a dimension having 200 mm of the vertical length (Y
direction) and 440 mm of the horizontal length (X direction)
(excluding the fitting salient and the fitting reentrant) of the
shape shown in FIG. 1, thereby the holding sealer sample was
obtained. The holding sealer sample which was obtained in the above
is set as an example 1. Also, a holding sealer sample was
manufactured in a method for placing the protective sheet on the
mat base member such that the direction having the maximum
extension of the PP non-woven fabric A is substantially parallel to
the long length direction of the holding sealer sample in the same
method in the example 1. This sample is set as a comparative
example 1.
[0062] Next, holding sealers of an example 2 in which PP non-woven
fabric B (product name: ELTAS, PO3020, Asahi-Kasei Seni) having
different expansion and contraction capabilities as the protective
sheet was used and a comparative example 2 were manufactured in the
same method as the example 1. In the example 2, the protective
sheet was placed such that the direction having the maximum
extension of the protective sheet is substantially parallel to the
short length of the holding sealer sample. In the comparative
example 2, the protective sheet was placed such that the direction
having the maximum extension of the protective sheet is
substantially parallel to the long length of the holding sealer
sample.
[0063] Further, holding sealers of an example 3 in which PP
non-woven fabric C (product name: ELTAS, PO3030, Asahi-Kasei Seni)
having different an expansion and contraction ability as the
protective sheet was used and a comparative example 3 were
manufactured in the same method as the example 1. In the example 3,
the protective sheet was placed such that the direction having the
maximum extension of the protective sheet is substantially parallel
to the short length of the holding sealer sample. In the
comparative example 3, the protective sheet was placed such that
the direction having the maximum extension of the protective sheet
is substantially parallel to the long length of the holding sealer
sample.
[0064] In addition, a holding sealer of a comparative example 4, in
which PET (polyethylene telephthalate) having different an
expansion and contraction capability and PE (polyethylene)
non-woven fabric D (product name: ELTAS, EW5015, Asahi-Kasei Seni)
as the protective sheet was used, was manufactured in the same
method as the example 1. In the comparative example 4, the
protective sheet was placed such that the direction having the
maximum extension of the protective sheet is substantially parallel
to the long length of the holding sealer sample.
[0065] Data like thickness, pulling strength, extension amount and
other characteristics of samples for evaluation concerning examples
1-3 and comparative examples 1-4 are shown in Table 1.
TABLE-US-00001 TABLE 1 MATERIAL THICKNESS OF OF RATIO OF PULLING
STRENGTH PROTECTIVE PROTECTIVE THICKNESS CIRCUMFERENTIAL (N/3 cm)
SHEET SHEET OF MAT DIFFEFENCE VERTICAL HORIZONTAL NO.
(SPECIFICATION) (mm) (mm) (%) DIRECTION DIRECTION EXAMPLE 1 PP 0.13
14.3 22.6 25.5 6.1 NONWOVEN FABRIC A EXAMPLE 2 PP 0.16 14.3 22.6
34.2 9.6 NONWOVEN FABRIC B EXAMPLE 3 PP 0.23 14.3 22.6 50.8 13.5
NONWOVEN FABRIC C COMPARATIVE PP 0.13 14.3 22.6 25.5 6.1 EXAMPLE 1
NONWOVEN FABRIC A COMPARATIVE PP 0.16 14.3 22.6 34.2 9.6 EXAMPLE 2
NONWOVEN FABRIC B COMPARATIVE PP 0.23 14.3 22.6 50.8 13.5 EXAMPLE 3
NONWOVEN FABRIC C COMPARATIVE PET + PE 0.08 14.1 22.2 22.1 6.2
EXAMPLE 4 NONWOVEN FABRIC RELATIONSHIP BETWEEN THE MAXIMUM
EXTENSION DIRECTION (HORIZONTAL DIRECTION) OF THE EXTENSION AMOUNT
PROTECTIVE SHEET RESULT (%) AND THE WINDING LEAKAGE OF VERTICAL
HORIZONTAL DIRECTION OF THE AMOUNT WINDING NO. DIRECTION DIRECTION
HOLDING SEALER (m cm/kPa/sec) EXAMINATION EXAMPLE 1 46.2 59.7
PERPENDICULAR 0.04 .largecircle. EXAMPLE 2 44.9 63.2 PERPENDICULAR
0.05 .largecircle. EXAMPLE 3 45.1 57.6 PERPENDICULAR 0.05
.largecircle. COMPARATIVE 46.2 59.7 PARALLEL 0.10 .largecircle.
EXAMPLE 1 COMPARATIVE 44.9 63.2 PARALLEL 0.12 .largecircle. EXAMPLE
2 COMPARATIVE 45.1 57.6 PARALLEL 0.12 .largecircle. EXAMPLE 3
COMPARATIVE 12.8 13.7 PARALLEL 0.19 X EXAMPLE 4 PP: POLYPROPYLENE,
PET: POLYETHYLENE TELEPHTHALATE, PE: POLYETHYLENE
[0066] In the Table 1, a ratio of circumferential difference (P) is
an index expressing the difference between an outer circumference
(LO) and an inner circumference (LI) of the holding sealer
occurring when the holding sealer is wound around. It is expressed
as the following formula.
P=(LO-LI)/LI.times.100 (1)
Also, the pulling strength and the extension amount for each
protective sheet were measured following the description in
"standard time examination" of JIS-L1906 (general length
fiber-non-woven fabric examination method).
[0067] Examination for Evaluating
[0068] Next, a leakage examination and a winding examination were
performed using each holding sealer sample manufactured in the
above method.
[0069] The leakage examination was performed as follows. First,
each holding sealer sample is wound around on a cylinder (a
non-hollow body) having an outer diameter 5 inches, and both ends
of the holding sealer sample are fitted and fixed on the cylinder.
Next, this unified member is forced into a metallic casing by the
press-fit means, and this resulting member is as a sample body. The
density of the holding sealer after forcing (that is, the measured
weight of the holding sealer before forcing/the thickness of the
holding sealer after forcing into the casing) was 0.45 g/cm.sup.3.
Then, the resulting member is placed on a tool having almost the
same inner diameter as the outer shape of the casing. Under this
condition, air which has a known pressure and speed is blown into
the sample body along an axis direction of the sample body from one
side of the sample body to the other side of the sample body. The
amount of air which is discharged from the sample body is measured
using a meter to measure the amount of air arriving on the other
side of the axis direction of the sample body. According to the
above examination, the leakage amount is calculated as follows.
[0070] The leakage amount (mcm/kPa/sec)=speed of the discharged air
(m/sec)/[inflow pressure (kPa)/length of sample in an inflow
direction (cm)]
[0071] Also, in the winding examination, it evaluated whether a
sample is cracked by observing with human eyes when each holding
sealer sample is wound around on the cylinder having the outer
diameter 5 inches, and both ends of the holding sealer sample are
fitted and fixed on the cylinder as the above.
[0072] Results of the Examination
[0073] Results of the leakage examination and the winding
examination for each sample are shown in Table 1. Based on results
of the leakage examination, it is recognized that the leakage
amount of the exhaust gas for the holding sealer of examples 1-3 is
advantageously decreased compared to the holding sealer of the
comparative examples 1-4. This is because that the direction
showing the maximum extension of the protective sheet is
substantially perpendicular to the winding direction for the
holding sealer of examples 1-3; thereby good deformation moderation
effect is provided.
[0074] On the other hand, based on results of the winding
examination, it is recognized that the winding capability of the
holding sealer does not so much depend on materials of the
protective sheet and the direction having its maximum extension and
cracks on the protective sheet does not occur even though the
direction having the maximum extension of the protective sheet is
either the short length direction or the long length direction of
the holding sealer. However, it is recognized that cracks on the
protective sheet occur for the holding sealer of the comparative
example 4 after the examination. This is because that the extension
amount for the winding direction of the protective sheet is smaller
than the ratio of circumferential difference (P). Thereby, it is
necessary that the extension amount for the winding direction of
the protective sheet be at least greater than the ratio of
circumferential difference (P).
INDUSTRIAL APPLICABILITY
[0075] The holding sealer and the exhaust gas processing device
according to the present invention are applicable to the exhaust
gas processing units and the like for vehicles.
[0076] The present invention is not limited to the specifically
disclosed embodiment, and variations and modifications may be made
without departing from the scope of the present invention.
[0077] The present application is based on Japanese priority
application No. 2006-228153 filed on Aug. 24, 2006, the entire
contents of which and JP 3072281 are hereby incorporated by
references.
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