U.S. patent application number 12/715939 was filed with the patent office on 2010-09-02 for conveyor and method of manufacturing absorbent article.
This patent application is currently assigned to UNICHARM CORPORATION. Invention is credited to Hiroki Yamamoto.
Application Number | 20100219224 12/715939 |
Document ID | / |
Family ID | 42666588 |
Filed Date | 2010-09-02 |
United States Patent
Application |
20100219224 |
Kind Code |
A1 |
Yamamoto; Hiroki |
September 2, 2010 |
CONVEYOR AND METHOD OF MANUFACTURING ABSORBENT ARTICLE
Abstract
A conveyor conveys a continuous stretchable web. The conveyor
includes a press mechanism configured to press the web in at least
a center region C in a cross direction perpendicular to a
conveyance direction of the web, or at least side edge regions S
located in positions shifted from the center region toward both
side edges of the web in the cross direction. The press mechanism
is provided in a position shifted from a conveyance plane R of the
web when viewed along a surface of the web in the cross
direction.
Inventors: |
Yamamoto; Hiroki;
(Kanonji-shi, JP) |
Correspondence
Address: |
LOWE HAUPTMAN HAM & BERNER, LLP
1700 DIAGONAL ROAD, SUITE 300
ALEXANDRIA
VA
22314
US
|
Assignee: |
UNICHARM CORPORATION
Ehime
JP
|
Family ID: |
42666588 |
Appl. No.: |
12/715939 |
Filed: |
March 2, 2010 |
Current U.S.
Class: |
226/1 ;
226/196.1 |
Current CPC
Class: |
B65H 2701/1716 20130101;
B65H 2801/57 20130101; B65H 23/28 20130101; B65H 2701/1864
20130101; B65H 45/22 20130101; B65H 37/06 20130101; B65H 37/04
20130101; B65H 2301/51242 20130101 |
Class at
Publication: |
226/1 ;
226/196.1 |
International
Class: |
B65H 20/00 20060101
B65H020/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 2, 2009 |
JP |
2009-048479 |
Feb 26, 2010 |
JP |
2010-042183 |
Claims
1. A conveyor for conveying a continuous stretchable web in a
conveyance direction, the web having, in a cross direction
perpendicular to the conveyance direction, a center region and side
edge regions on opposite sides of the center region, said conveyor
comprising: a conveying mechanism for conveying the web in a
conveyance plane; and a press mechanism for pressing the web in at
least one of the center or side edge region of the web, to deflect
the web off the conveyance plane and cause the web to be stretched
in the cross direction.
2. The conveyor according to claim 1, wherein the press mechanism
includes a press face to be in contact with the web, and the press
face is in a straight-line form when viewed along the surface of
the web in the conveyance direction.
3. The conveyor according to claim 1, wherein the press mechanism
includes a press face to be in contact with the web, and the press
face is in a curved form when viewed along the surface of the web
in the conveyance direction.
4. The conveyor according to claim 3, further comprising at least
two support points for supporting the web while the press face is
pressing the center region and the side edge regions of the
web.
5. The conveyor according to claim 1, wherein the press mechanism
includes, in the cross direction: a center press face adapted to be
in contact with the center region of the web; and side edge press
faces on opposite sides of the center press face and being adapted
to be in contact with the side edge regions, respectively, and when
viewed in the conveyance direction, each of the side edge press
faces extends from an end of the center press face obliquely away
from the web.
6. The conveyor according to claim 1, wherein the press mechanism
is provided upstream of the conveyor mechanism in the conveyance
direction of the web.
7. The conveyor according to claim 1, wherein the press mechanism
includes a press face to be in contact with the web, and the press
face has a width in the cross direction which is larger on a
downstream side in the conveyance direction of the web than on an
upstream side.
8. A method of manufacturing absorbent articles, the method
comprising: conveying, in a conveyance plane, a continuous web to
be processed by a plurality of processes into the absorbent
articles, the web having, in a cross direction perpendicular to a
conveyance direction, a center region and side edge regions on
opposite sides of the center region; and pressing the web in at
least one of the center or side edge region of the web, to deflect
the web off the conveyance plane.
9. The method according to claim 8, wherein the conveying and the
pressing are performed before any one of said processes.
10. The method of manufacturing an absorbent article according to
claim 9, wherein the web is not stretchable, and in the process
step, a sheet stretchable in the cross direction of the web is
stacked on the web.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a conveyor configured to
convey a continuous stretchable web, and a method of manufacturing
an absorbent article.
BACKGROUND ART
[0002] A method of manufacturing an absorbent article such as a
pants-type diaper, a sanitary napkin and a panty liner is
implemented in an assembly line, in general. For instance, a
continuous web including a continuum of top sheets and a continuum
of bottom surface sheets to form absorbent articles is conveyed
under tension in a web conveyance direction by a conveyor (for
example, see PTL 1). Then, component members such as a gather
(elastic member) and a waterproof film are placed on the web being
conveyed under tension in the web conveyance direction.
[0003] A web with stretchable component members, such as a gather
and a waterproof film, arranged thereon sometimes extends or
shrinks in a cross direction (a web width direction) perpendicular
to the web conveyance direction. In particular, in a system in
which a web is conveyed in the web conveyance direction in a state
where a pair of waistline portions to be eventually fitted to the
waist of a wearer are arranged to extend in the web conveyance
direction (as known as a crosswise conveyor system), the web during
conveyance is often asymmetrical with respect to the center line
that bisects the width of the web, and sometimes shrinks toward the
center in the web width direction.
[0004] To address this problem, a conveyor has been disclosed in
Japanese Patent Application Publication No. 2003-145485 to prevent
a web from shrinking toward the center in a width direction. The
conveyer includes an endless belt configured to rotate between
multiple pairs of rollers, a drive mechanism configured to rotate
the belt, and a suction mechanism configured to suck the web down
onto the belt through multiple suction holes formed in the belt.
The suction mechanism causes the web to stick to the belt through
the suction holes.
[0005] The inventors have discovered that once a web shrinks toward
the center in the width direction, the web is stuck to the belt in
the shrunken state. Consequently, the web has one or more creases
therein in some cases. Such creases need to be smoothed out to
avoid manufacturing defects.
[0006] Under these circumstances, the present invention is aimed to
provide a conveyor and a method of manufacturing an absorbent
article which are capable of surely smoothing out a crease
generated in a stretchable web even when the crease is generated in
the web.
Citation List
Patent Literature
PTL 1. Japanese Patent Application Publication No. 2003-145485 (pp.
2 to 4, FIGS. 1 and 2)
SUMMARY
[0007] To solve the above-described problem, the present invention
has the following aspects.
[0008] In an aspect, a conveyor for conveying a continuous
stretchable web in a conveyance direction is provided. The web has,
in a cross direction perpendicular to the conveyance direction, a
center region and side edge regions on opposite sides of the center
region. The conveyor comprises a conveying mechanism for conveying
the web in a conveyance plane; and a press mechanism for pressing
the web in at least one of the center or side edge region of the
web, to deflect the web off the conveyance plane and cause the web
to be stretched in the cross direction.
[0009] In another aspect, a method of manufacturing absorbent
articles is provided. The method comprises conveying, in a
conveyance plane, a continuous web to be processed by a plurality
of processes into the absorbent article. The web has, in a cross
direction perpendicular to a conveyance direction, a center region
and side edge regions on opposite sides of the center region. The
method further comprises pressing the web in at least one of the
center or side edge region of the web, to deflect the web off the
conveyance plane.
[0010] To solve the above-described problem, the present invention
has the following aspects. A aspect of the present invention
provides a conveyor that conveys a long stretchable web, comprising
a press mechanism configured to press the web in at least a center
region in a cross direction perpendicular to a conveyance direction
of the web, or at least side edge regions located in positions
shifted from the center region toward both side edges of the web in
the cross direction, wherein the press mechanism is provided in a
position shifted from a conveyance plane of the web when viewed
along a surface of the web in the cross direction.
[0011] According to the aspect of the present invention, there can
be provided a conveyor and a method of manufacturing an absorbent
article which are capable of surely smoothing out a crease
generated in a stretchable web even when the crease is generated in
the web.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a partially cutaway, perspective view showing an
absorbent article according to one or more embodiments.
[0013] FIG. 2 is a diagram for explaining a relevant part of a
method of manufacturing absorbent articles according to one or more
embodiments.
[0014] FIG. 3 is a perspective view of a relevant part of a
conveyor according to one or more embodiments.
[0015] FIG. 4 is a side view of a press mechanism of the conveyor
of FIG. 3.
[0016] FIG. 5 is a front view of the press mechanism.
[0017] FIG. 6 is a top plan view of a press board of the press
mechanism.
[0018] FIG. 7 is a perspective view of a press mechanism according
to a Modified Example 1.
[0019] FIGS. 8A and 8B are front views of a press mechanism
according to a Modified Example 2.
[0020] FIG. 9 is a front view of a press mechanism according to a
Modified Example 3.
[0021] FIG. 10 is a front view of a press mechanism according to a
Modified Example 4.
DETAILED DESCRIPTION
[0022] Hereinafter, a conveyor and a method of manufacturing an
absorbent article according to one or more embodiments of the
present invention will be described with reference to the
accompanying drawings. Note that, in the following description and
in the drawings, the same or similar reference signs denote the
same or similar elements and portions. In addition, it should be
also noted that the drawings are schematic, and are not to scale
unless otherwise specified. For this reason, the specific
dimensions should be determined in consideration of the following
descriptions. Moreover, the drawings do not necessarily reflect the
real-life dimensional relationships and ratios of components.
[0023] Firstly, a configuration of an absorbent article 1 according
to one or more embodiments will be explained with reference to FIG.
1 which is a partially cutaway perspective view showing the
absorbent article 1. In this particularly illustrated embodiment,
the absorbent article 1 is a disposable pants-type diaper for
adults.
[0024] As shown in FIG. 1, the absorbent article 1 mainly includes
a top sheet 2, a back sheet 3, an absorber 4 and a waterproof sheet
5.
[0025] The top sheet 2 is adapted to come into contact with the
skin of a person to wear the absorbent article 1 (hereinafter,
"wearer"). The top sheet 2 is made of a liquid permeable sheet such
as a nonwoven fabric or a perforated plastic film. The back sheet 3
is provided outside the top sheet 2 (on the side farther from the
wearer). The back sheet 3 is made of a nonwoven fabric or the
like.
[0026] The absorber 4 is provided between the top sheet 2 and the
back sheet 3, for absorbing excretion discharged from the wearer.
The absorber 4 is made of a mixture of g pulp and superabsorbent
polymer particles, or the like. The waterproof sheet 5 is provided
between the back sheet 3 and the absorber 4, for blocking the
permeation of the excretion from the wearer to the outside of the
absorbent article 1. The waterproof sheet 5 is made of a liquid
impermeable sheet.
[0027] The absorbent article 1 is provided with the top sheet 2,
the absorber 4, the waterproof sheet 5 and the back sheet 3 in
order, from the skin side of the wearer.
[0028] The absorbent article 1 thus configured includes, in
combination, a front waistline portion 10 to be fitted to the front
waist of a wearer, a back waistline portion 20 to be fitted to the
back waist of the wearer, and a crotch portion 30 to be fitted to
the crotch of the wearer. Incidentally, leg-surrounding openings 40
into which the legs of the wearer are inserted are formed on both
sides of the crotch portion 30.
[0029] The front waistline portion 10 and the back waistline
portion 20 are joined together by joint portions 50, and thereby
form a waist opening to be fit around the body of the wearer. A
waist gather 6A made of a stretchable rubber strand or the like is
provided to an entire peripheral edge of the front waistline
portion 10 and the back waistline portion 20.
[0030] For example, to make the front waistline portion 10 and the
back waistline portion 20 stretchable in the cross direction
perpendicular to the front-to-back direction from the front
waistline portion 10 toward the back waistline portion 20, the
front waistline portion 10 and the back waistline portion 20 may be
provided with the waist gather 6A, or may themselves be made of a
stretchable sheet.
[0031] The crotch portion 30 is provided between the front
waistline portion 10 and the back waistline portion 20. Leg gathers
6B made of stretchable rubber strands or the like are provided on
both sides of the crotch portion 30.
[0032] For example, to make the crotch portion 30 stretchable in
the leg-encircling direction, the crotch portion 30 may be provided
with the leg gathers 6B, or may itself be made of a stretchable
sheet.
[0033] Secondly, a method of manufacturing absorbent articles, such
as the aforementioned absorbent article 1, according to one or more
embodiments will be explained with reference to FIG. 2 which is a
diagram for explaining a relevant part of the absorbent article
manufacturing method.
[0034] As shown in FIG. 2, the method of manufacturing absorbent
articles includes at least a waistline forming step S1, an absorber
transferring step S2, a leg-surrounding forming step S3, a folding
step S4, a joining step S5 and a cutting step S6.
[0035] In the waistline forming step S1, gathers (waist gathers 6A
and/or leg gathers 6B) are placed between a web 7A and a web 7B,
and thereby a web 7 prepared to form the front waistline portion 10
and the back waistline portion 20 is formed.
[0036] Note that the web 7 (webs 7A, 7B) during conveyance is
stretchable in a width direction CD (cross direction) perpendicular
to a conveyance direction MD of the web 7. In addition, the web 7
is asymmetrical with respect to a center line CL that bisects a
width in the width direction CD of the web 7 and extends in the
conveyance direction MD of the web 7.
[0037] In the absorber transferring step S2, a crotch portion
member 30A to form the crotch portion 30 is transferred onto the
web 7, more specifically, between the front waistline portion 10
and the back waistline portion 20 after the waistline forming step
S1. Here, the crotch portion member 30A includes the back sheet 3
and the absorber 4.
[0038] In the leg-surrounding forming step S3, the leg-surrounding
openings 40 (so-called leg holes) are formed by cutting the web 7
(webs 7A, 7B) after the absorber transferring step S2. Here, the
formation of the leg-surrounding openings 40 does not necessarily
involve cutting only the web 7A and the web 7B, but may involve
cutting, together with the web 7A and the web 7B, the back sheet 3
constituting the crotch portion member 30A.
[0039] Note that the absorber transferring step S2 and the
leg-surrounding forming step S3 may be performed in the reverse
order.
[0040] In the folding step S4, the web 7 is folded into two parts
along a folding line extending in the conveyance direction MD of
the web 7 by bringing a side edge 10A of the front waistline
portion 10 toward a side edge 20A of the back waistline portion 20,
after the leg-surrounding forming step S3.
[0041] Note that, in this particularly illustrated embodiment, the
folding line is the center line CL. However, the folding line is
not necessarily the center line CL, and may be shifted from the
center line CL toward either of the side edge 10A and the side edge
20A.
[0042] In the joining step S5, the folded parts of the web 7 are
joined together in joint regions 50A through ultrasonic treatment
or heat treatment after the folding step S4. The joint region 50A
extends in the conveyance direction MD across an imaginary line SL
that indicates a to-be-cut position and extends in the width
direction CD.
[0043] In the cutting step S6, the web 7 joined in the joint
regions 50A is cut along the imaginary lines SL after the joining
step S5. Thereby, the absorbent article 1 is manufactured.
[0044] Here, the method of manufacturing absorbent articles
includes conveying steps between the steps (S1 to S6). In each of
the conveying steps, the web 7 to be processed into the absorbent
article 1 is conveyed by a conveyor 100, which will be described
later. In other words, the conveying step is performed before each
of the process steps (S1 to S6) in which the web 7 is
processed.
[0045] Hereinafter, a configuration of the conveyor 100 used in the
conveying steps will be described with reference to FIG. 3 which is
a perspective view of a relevant part of the conveyor 100 according
to one or more embodiments.
[0046] Since the conveyors 100 used in the conveying steps before
the respective steps (51 to S6) have the same configuration, the
description will be provided by taking, as an example, the conveyor
100 that conveys the web 7 before the waistline forming step
S1.
[0047] As shown in FIG. 3, the conveyor 100 conveys the web 7 under
tension in the conveyance direction MD of the web 7. The conveyor
100 includes at least a press mechanism 110 and a conveyor
mechanism 120. A configuration of the press mechanism 110 will be
described later.
[0048] The conveyor mechanism 120 is provided on the opposite side
of the web 7 from the press mechanism 110. The conveyor mechanism
120 is provided downstream of the press mechanism 110 in the
conveyance direction MD. The conveyor mechanism 120 includes a belt
121, a drive unit 122, a suction unit 123 and an edge press unit
124.
[0049] The belt 121 is an endless belt configured to rotate around
plural rollers (for example, a driving roller 122A and an
unillustrated roller) while having the web 7 placed thereon. The
belt 121 is provided with multiple suction holes 121A through which
the web 7 is sucked.
[0050] The drive unit 122 rotates the belt 121. The drive unit 122
includes two or more rollers (unillustrated) and the driving roller
122A. The drive unit 122 includes a motor configured to rotate the
driving roller 122A through a shaft, and the like. The suction unit
123 sucks air through the suction holes 121A which will be
described later. In other words, the suction unit 123 causes the
web 7 during conveyance to stick to the belt 121.
[0051] The edge press unit 124 presses the side edges 10A and 20A
of the web 7 against the belt 121. The edge press unit 124 includes
a first press portion 124A arranged along the side edge 10A of the
web 7 and a second press portion 124B arranged along the side edge
20A of the web 7. The first press portion 124A and the second press
portion 124B are coupled to each other with a pipe 125.
[0052] Hereinafter, a configuration of the press mechanism 110
according to one or more embodiments will be described with
reference to FIGS. 3 to 6. FIG. 4 is a side view of the press
mechanism 100 as seen in the direction of arrow A in FIG. 3. FIG. 5
is a front view of the press mechanism 100 as seen in the direction
of arrow B in FIG. 3. FIG. 6 is a top plan view of a press board
111 of the press mechanism.
[0053] As shown in FIG. 3, the press mechanism 110 is provided on
the opposite side of the web 7 from the conveyor mechanism 120. The
press mechanism 110 is located close to the belt 121 rotating
around the drive unit 122, and upstream of the conveyor mechanism
120 in the conveyance direction MD of the web 7.
[0054] The press mechanism 110 is provided in a position shifted
from a conveyance plane R in which the web 7 is to be conveyed by
the belt 121. More specifically, the press mechanism 110 is located
below the conveyance plane R defined by belt 121.
[0055] The press mechanism 110 presses downward the web 7 in a
center region C in the width direction CD of the web 7 and/or in at
least one of side edge regions S located in positions shifted from
the central region C toward the side edges in the width direction
CD of the web 7. In other words, the side edge regions S are
located on opposite sides of the center region as seen in the cross
direction CD. In this particularly illustrated embodiment, the
press mechanism 110 presses downward the side edge regions S,
except for the side edge 10A and the side edge 20A of the web 7,
and therefore is not in contact with any of the side edges (the
side edge 10A or the side edge 20A).
[0056] More specifically, as shown in FIGS. 4 and 5, the press
mechanism 110 includes a press board 111. The press board 111 is
made of polytetrafluoroethylene or the like. The press board 111 is
bent when viewed along the surface of the web 7 in the width
direction CD. The press board 111 is fixed through a fixed frame
112 to a support bar 113 extending in the width direction CD.
[0057] The press board 111 includes a press face 111A to be in
contact with the web 7. The press face 111A is in a straight-line
form when viewed along the surface of the web 7 in the conveyance
direction MD of the web 7 (i.e., viewed in a direction
perpendicular to the support bar 113).
[0058] As shown in FIG. 6, the press board 111 has a width (w) in
the width direction CD which becomes larger, more particularly,
gradually larger, from an upstream side to a downstream side in the
conveyance direction MD of the web 7. More precisely, a downstream
side width (w1) in the press board 111 is larger than an upstream
side width (w2) in the press board 111. It should be noted that the
downstream side width (w1) in the press board 111 is larger than
the width of the web 7, and therefore, as best seen in FIG. 3, is
located above the edges 10A, 20A of the web 7 to flatten out the
edges 10A, 20A when the web 7 emerges from under the press board
111.
[0059] The press mechanism 110 is provided in the position shifted
from the conveyance plane R of the web 7 when viewed along the
surface of the web 7 in the width direction CD, and presses the
center region C and the side edge regions S. Unlike the case where
the web 7 is not pressed, such pressing deflects the web 7 off the
conveyance plane R and causes the web 7 during conveyance to be
stretched toward outer sides in the width direction CD when passing
under the press mechanism 110. Therefore, even when a crease is
generated in the web 7 during conveyance, such crease is surely
smoothed out. It should be noted that the center region S of the
web 7 is deflected further away from the conveyance plane R than
the side edge regions S of the web.
[0060] In essence, any crease in the web 7 is smoothed out by the
press mechanism 110 before the web 7 reaches the conveyor mechanism
120, and thus the edge press unit 124 presses the side edges 10A
and 20 A of the web 7 which has no crease. In this way, the web 7
can be conveyed surely in a state free from any crease.
[0061] The edge press unit 124 provided in the conveyor mechanism
120 has a first press unit 124A, a second press unit 124B and a
pipe 125. The first press unit 124A and the second press unit 124B
press the side edges 10A and 20A of the web 7 toward the belt 121.
The side edges 10A and 20A of the web 7 are pressed toward the belt
121 by the edge press unit 124. In this way, the web 7 can be
surely conveyed in a state free from any crease in the conveyor
mechanism 120 as well.
[0062] As disclosed herein, the performing of the conveying step
before (immediately before, in particular) each of the process
steps (S1 to S6) in which the web 7 is processed enables the
process to be applied to the web 7 having no crease. Thus, the
conveying step can surely reduce manufacturing defects of the
absorbent articles 1 and prevent the manufacturing line from
stopping.
[0063] As disclosed herein, the press face 111A is in a
straight-line form when viewed in the conveyance direction MD of
the web 7. With the press face 111A, the web 7 is stretched to be
in a planar state immediately before each process (e.g., any of
S1-S6). In other words, the process is applied to the web 7 which
has been tuned into and then kept in the planar state by the press
face 111A. Consequently, manufacturing defects of the absorbent
articles 1 can be reduced more surely.
[0064] As disclosed herein, the conveyor 100 includes the conveyor
mechanism 120 in addition to the press mechanism 110. The conveyor
mechanism 120 can surely prevent the web 7 after passing under the
press mechanism 110 from shrinking toward the center in the width
direction CD. In particular, the edge press unit 124 presses the
side edge 10A and the side edge 20A of the web 7 against the belt
121, whereby the stretchable web 7 can be more surely prevented
from shrinking toward the center in the width direction CD. As a
result, creases can be more surely prevented from occurring in the
web 7.
[0065] As disclosed herein, the width (w) of the press board 111 in
the width direction CD is larger on the downstream side than on the
upstream side. With this configuration, when the web 7 during
conveyance passes under the press mechanism 110, the web 7 in
contact with the press board 111 is stretched outward in the width
direction CD by the press board 111. Thus, any crease generated in
the web 7 can be even more surely smoothed out.
MODIFIED EXAMPLES
[0066] The press mechanism 110 according to the foregoing
description may be modified as follows. Here, the description will
be provided mainly for the differences from the foregoing
description, with the same or similar reference signs denoting the
same or similar elements.
Modified Example 1
[0067] Firstly, a configuration of a press mechanism 210A according
to a Modified Example 1 will be described with reference to FIG. 7
which is a perspective view showing the press mechanism 210A
according to the Modified Example 1.
[0068] In the foregoing description, the press mechanism 110
includes the press board 111. In contrast, in the Modified Example
1, the press mechanism 210A includes a body roller 114 in a
cylindrical shape, as shown in FIG. 7.
[0069] More specifically, the body roller 114 is attached to a
shaft 115 extending in the width direction CD of the web 7. Here,
the body roller 114 may be configured to rotate or not to rotate
along with conveyance of the web 7. In some embodiments, the body
roller 114 is a passive roller that follows the movement of the web
7. In other embodiments, the body roller 114 is an actively driven
roller that may rotate with, or against, the conveyance of the web
7 for varying crease smoothing effects. The body roller 114
includes a press face 114A to be in contact with the web 7.
Modified Example 2
[0070] Secondly, a configuration of a press mechanism 210B
according to a Modified Example 2 will be described with reference
to FIGS. 8A and 8B which are front views of the press mechanism
210B according to the Modified Example 2.
[0071] In the foregoing description, it is described that the press
mechanism 110 presses downward a whole surface including the center
region C and the side edge regions S of the web 7. In contrast, in
the Modified Example 2, the press mechanism 210B presses downward
only the center region C of the web 7 as shown in FIG. 8A. Here,
the center regions C are regions including the center portion of
the width direction CD of the web 7. The side edge regions S are
regions with which the press mechanism 210B is not in contact.
[0072] The press mechanism 210B does not necessarily have to press
downward only the center region C of the web 7, and, instead, may
press downward only the side edge regions S as shown in FIG. 8B.
While it is shown in FIG. 8B that the edges of web 7 (i.e., edges
10A, 20A) are not in contact with the press mechanism 210B, in some
unshown embodiments, at least one of the edges of the web 7 is in
contact with the press mechanism 210B.
[0073] The web 7 is stretchable. Therefore, when a force is applied
to an arbitrary region in the width direction of the web 7, a
tension can be applied to the web 7.
[0074] Moreover, in the conveyor 100, a location of the web 7
relative to the conveyor 100 is decided based on a centerline in
the width direction of the web 7. Accordingly, as in the embodiment
shown in FIG. 8 (b), applying a force to the edge portions (side
edges 10A and 20A) of the outside in the width direction of the web
7 prevents the edge portions from shrinking in the inside of the
width direction. Thus, the web 7 to be conveyed is stabilized.
[0075] Moreover, the press mechanism 210B may be formed of only the
body roller 114, or may be formed of only the press board 111 as
described above. In some embodiments, the body roller 114 and the
press board 111 are used together in the same press mechanism 210B,
e.g., by arranging the press board 111 in the position illustrated
in FIG. 8A and, at the same time, arranging two body rollers 114 in
the position illustrated in FIG. 8B. In such embodiments, the press
board 111 can be upstream or downstream of the body rollers 114.
Other arrangements are within the scope of this disclosure.
Modified Example 3
[0076] Thirdly, a configuration of a press mechanism 210C according
to a Modified Example 3 will be described with reference to FIG. 9
which is a front view of the press mechanism 210C according to the
Modified Example 3.
[0077] In the foregoing description, the press face 111A is in the
straight-line form when viewed in the conveyance direction MD of
the web 7. In contrast, in the Modified Example 3, the press face
114A is in a curved form when viewed in the conveyance direction MD
of the web 7, as shown in FIG. 9.
[0078] Bending points 111B and 111C are formed on the press face
114A in cross sectional surface seen from the conveyance direction
MD of the web 7. Since the web 7 is conveyed at least two points
(bending points 111B and 111C) of the web 7 are supported, it is
possible to prevent the web 7 from traveling in a meandering
manner.
[0079] Moreover, the press mechanism 210C may be formed of only the
body roller 114 or only the press board 111 as described above.
Modified Example 4
[0080] Fourthly, a configuration of a press mechanism 210D
according to a Modified Example 4 will be described with reference
to FIG. 10 which is a front view of the press mechanism 210D
according to the Modified Example 4.
[0081] In the foregoing description, the press face 111A is in the
straight-line form when viewed in the conveyance direction MD of
the web 7. In contrast, in the Modified Example 4, the press face
114A is bent when viewed in the conveyance direction MD of the web
7, as shown in FIG. 10.
[0082] More specifically, the press mechanism 210D includes a
center press face 211 and a pair of side edge press faces 212. The
center press face 211 presses the center region C. The pair of the
side edge press faces 212 are located next to the center press face
211, more specifically, at both sides of the center press face 211
in the width direction CD of the web 7, and press the side edge
regions S, respectively. The side edge press faces 212 are each
extends from an end 212A of the center press face 211, obliquely
away from the web 7 (upward, in short) when viewed in the
conveyance direction MD of the web 7.
[0083] Moreover, the press mechanism 210D may be formed of only the
body roller 114 or may be formed of only the press board 111 as
described above.
Further Embodiments
[0084] As described above, the details of several embodiments have
been exemplarily disclosed. It should not be understood that the
description and drawings constituting part of this disclosure limit
the present invention. Based on this disclosure, those skilled in
the art may come up with various alternative embodiments, examples
and operation techniques.
[0085] For example, the following additional embodiments can be
envisaged. Specifically, the absorbent article 1 has been described
as including the front waistline portion 10, the back waistline
portion 20 and the crotch portion 30. The absorbent article 1 is
not limited to this configuration, but maybe formed entirely as a
single portion. In this case, needless to say, a different method
of manufacturing such an absorbent article is employed.
[0086] Additionally, the description has been provided for the
conveyor 100 used in the manufacturing of a pants-type disposal
diaper. However, the conveyor 100 is not limited to such use. For
example, the conveyor 100 may be used to manufacture another
product such as an open-type disposal diaper, a sanitary napkin and
a panty liner, for example. In other words, the conveyor 100 maybe
used for the conveyance of any web 7 that is stretchable in the
width direction CD of the web, not necessarily for the
manufacturing of the absorbent article 1. As long as the conveyor
100 conveys a stretchable web 7, the conveyor 100 may be used
between steps other than the steps described with respect to FIG.
2.
[0087] Moreover, the description has been provided for the conveyor
100 used to convey a single web 7. However, the conveyor 100 is not
limited to such use. For example, when a web including a continuum
of the front waistline portions 10 and a web including a continuum
of the back waistline portions 20 are conveyed simultaneously, a
single conveyor 100 may be provided for each or both of the webs.
In addition, multiple conveyors 100 may be provided between any two
of the process steps.
[0088] Further, the press mechanism 110 has been described as the
one pressing the web 7 downward, but it is not limited to this
configuration. The press mechanism 110 may press the web 7 upward,
for example.
[0089] Additionally, the press mechanism 110 has been described as
the one located below the belt 121, which is in contact with the
web 7, when viewed in the axial direction of the drive unit 122,
but it is not limited to this configuration. Instead, the press
mechanism 110 may be located above the belt 121, for, e.g.,
pressing the web 7 upward.
[0090] Furthermore, the press mechanism 110 has been described as
the one pressing the side edge regions S, except for the side edge
10A and the side edge 20A, but it is not limited to this
configuration. The press mechanism 110 may press the side edge
regions S including the side edge 10A and the side edge 20A,
apparently.
[0091] As described above, the present invention naturally includes
various embodiments which are not described herein. Accordingly,
the technical scope of the present invention should be determined
only by the matters to define the invention in the scope of claims
regarded as appropriate based on the description.
[0092] The entire contents of Japanese Patent Applications
2009-048479 (filed on Mar. 2, 2009) and 2010-042183 (filed on Feb.
26, 2010) are incorporated herein by reference.
INDUSTRIAL APPLICABILITY
[0093] Therefore, since the conveyor and method of manufacturing
absorbent article of the present invention is capable of surely
smoothing out a crease generated in a stretchable web even when the
crease is generated in the web, it is useful in manufacturing
technology for absorbent articles.
REFERENCE SIGNS LIST
[0094] 1 absorbent article
[0095] 2 top sheet
[0096] 3 back sheet
[0097] 4 absorber
[0098] 5 waterproof sheet
[0099] 6 gather
[0100] 6A waist gather
[0101] 6B leg gather
[0102] 7, 7A, 7B web
[0103] 10 front waistline portion
[0104] 10A side edge
[0105] 20 back waistline portion
[0106] 20A side edge
[0107] 30 crotch portion
[0108] 30A crotch portion member
[0109] 40 leg-surrounding opening
[0110] 50 joint portions
[0111] 50A joint region
[0112] 60 waist opening
[0113] 100 conveyor
[0114] 110 (210A to 210D) press mechanism
[0115] 111 press board
[0116] 111A press face
[0117] 112 fixed frame
[0118] 113 support bar
[0119] 114 body roller
[0120] 114A press face
[0121] 115 shaft core
[0122] 120 conveyor mechanism
[0123] 121 belt
[0124] 121A suction hole
[0125] 122 drive unit
[0126] 122A driving roller
[0127] 123 suction unit
[0128] 124 edge press unit
[0129] 124A first press portion
[0130] 124B second press portion
[0131] 125 pipe
* * * * *