U.S. patent application number 11/500639 was filed with the patent office on 2007-04-19 for adhesive seam and method and apparatus for its manufacture.
This patent application is currently assigned to Cupid Foundations, Inc.. Invention is credited to Anthony Angelino, Ronald Boser, David Welsch.
Application Number | 20070084390 11/500639 |
Document ID | / |
Family ID | 37900204 |
Filed Date | 2007-04-19 |
United States Patent
Application |
20070084390 |
Kind Code |
A1 |
Angelino; Anthony ; et
al. |
April 19, 2007 |
Adhesive seam and method and apparatus for its manufacture
Abstract
A garment seam is formed between two fabric panels by abutting
the edges of at least two panels and placing a strip of material
carrying adhesive on the abutted edges to form the seam. The fabric
panels have opposing major surfaces, the edges of the fabric panels
being minor surfaces. The strip of material is applied on at least
one major surface of the abutted fabric panels, but is optionally
applied to both major surfaces of the abutted fabric panels. The
strip of material is preferably thinner than the fabric panels. In
some embodiments, the adhesive is a thermosetting adhesive that is
applied on the strip of material in liquid form. A seam
manufactured according to the present invention is less detectable
through clothing than conventional multi-ply seams. Also the
adhesive seam enables the manufacturer to tailor the garment to
provide support or shape in a particular area (i.e. the area of the
seam) in addition to providing the desirable smooth appearance. For
example, when used in a brassiere (bra) cup, the seam allows the
garment to be designed to provide optimal comfort, shape and
support to the wearer.
Inventors: |
Angelino; Anthony; (Edmond,
OK) ; Boser; Ronald; (Port St. Lucie, FL) ;
Welsch; David; (Livingston, NJ) |
Correspondence
Address: |
LERNER, DAVID, LITTENBERG,;KRUMHOLZ & MENTLIK
600 SOUTH AVENUE WEST
WESTFIELD
NJ
07090
US
|
Assignee: |
Cupid Foundations, Inc.
New York
NY
|
Family ID: |
37900204 |
Appl. No.: |
11/500639 |
Filed: |
August 8, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60717679 |
Sep 16, 2005 |
|
|
|
Current U.S.
Class: |
112/475.01 |
Current CPC
Class: |
B29C 66/8416 20130101;
B29C 66/83431 20130101; B29C 66/93451 20130101; B29C 65/526
20130101; A41D 27/245 20130101; B29C 65/483 20130101; B29C 65/484
20130101; B29C 65/522 20130101; B29C 66/872 20130101; B29C 66/8242
20130101; B29C 65/5042 20130101; B29C 66/43 20130101; B29C 66/729
20130101; B29C 66/00141 20130101; B29K 2311/10 20130101; B29C
65/524 20130101; B29C 66/73921 20130101; B29C 66/1142 20130101;
B29C 66/949 20130101; B29K 2075/00 20130101; A41C 5/00 20130101;
B29C 66/91931 20130101; B29C 66/919 20130101; B29C 66/954 20130101;
B29C 66/71 20130101; B29L 2031/4885 20130101; B29C 66/91933
20130101; B29C 65/7802 20130101; B29C 66/727 20130101; B29C 65/4845
20130101; B29C 66/8221 20130101; B29C 66/91411 20130101; B29C
66/8746 20130101; B29C 65/1406 20130101; B29K 2067/00 20130101;
B29K 2077/00 20130101; B29C 65/4815 20130101; B29C 66/8227
20130101; B29C 65/5092 20130101; B29C 66/71 20130101; B29K 2077/00
20130101; B29C 66/71 20130101; B29K 2075/00 20130101; B29C 66/71
20130101; B29K 2067/00 20130101 |
Class at
Publication: |
112/475.01 |
International
Class: |
D05B 1/00 20060101
D05B001/00 |
Claims
1. A method for forming a seam at an interface between at least two
panels of fabric, each panel having at least one edge comprising:
bringing into abutted alignment the edges of the at least two
fabric panels, thereby defining an interface region; applying
liquid adhesive onto the interface region; applying a material
strip along the interface region; and curing the adhesive to form
an adhesive seam.
2. The method of claim 1 wherein each of the at least two fabric
panels has a first side and a second side and wherein a first
adhesive seam is formed on the interface on the first side and a
second adhesive seam is formed on the interface on the second
side.
3. The method of claim 1 wherein the fabric panels are made of a
material selected from the group consisting of natural fibers,
synthetic materials and blends of natural fibers and synthetic
materials.
4. The method of claim 3 where in the synthetic fibers are selected
from the group consisting of polyester, rayon, polyurethane foam,
spandex and nylon.
5. The method of claim 3 wherein the natural fibers are selected
from the group consisting of cotton and wool.
6. The method of claim 1 wherein the liquid adhesive is selected
from the group consisting of thermosetting adhesive, thermoplastic
adhesive and radiation-curable adhesive.
7. The method of claim 1 wherein the liquid adhesive is applied
onto the material strip and the material strip carrying the liquid
adhesive is applied along the interface.
8. The method of claim 3 wherein the fabric panels are synthetic
materials selected from the group consisting of fiberfill and
polyurethane foam having a thickness of at least 5 mils.
9. The method of claim 8 further comprising placing liquid adhesive
on the edges of the fabric panels before the edges are brought into
abutted alignment to form the interface region.
10. The method of claim 1 further comprising applying a paper
backing to the material strip before the material strip is applied
to the interface.
11. The method of claim 10 further comprising removing the paper
backing from the material strip before the liquid adhesive is
substantially cured.
12. The method of claim 8 wherein the adhesive is at least
partially cured before the step of removing the paper backing.
13. The method of claim 1 wherein the adhesive is at least
partially cured by exposing the adhesive to moist ambient air.
14. The method of claim 1 further comprising placing the seam on a
contoured surface that substantially mimics the contour of the
adhesive seam during at least some portion of the curing step.
15. The method of claim 1 wherein the thickness of the strip of
material is thicker than the thickness of the adhesive applied
thereon.
16. The method of claim 1 wherein the fabric panels are
calendared.
17. The method of claim 1 wherein the fabric panels are finished
and further comprising the step of selecting an adhesive that
adheres to the fabric panels with the finish thereon.
18. The method of claim 17 wherein the finish and adhesive are both
water-based.
19. The method of claim 17 wherein the finish and adhesive are both
hydrophobic.
20. The method of claim 1 further comprising cutting fabric to form
the panels.
21. The method of claim 20 wherein the step of cutting is selected
from the group consisting of Gerber cutting, die cutting, sonic
cutting, hydro cutting and laser cutting.
22. The method of claim 1 wherein the fabric panels are
substantially the same thickness.
23. The method of claim 1 wherein the adhesive is applied to the
interface region by one of either spray coating or nozzle
coating.
24. The method of claim 7 wherein the adhesive is applied to the
material strip by roller coating.
25. The method of claim 1 wherein the material strip has a
thickness of about 1 mil to about 8 mils.
26. The method of claim 1 wherein the liquid adhesive is stored in
an inert atmosphere prior to applying the adhesive to the material
strip.
27. The method of claim 26 wherein the inert atmosphere is selected
from the group consisting of nitrogen, argon and super-dried
air.
28. The method of claim 1 wherein the uncured liquid adhesive melts
at a temperature in the range of about 220.degree. F. to about
280.degree. F.
29. The method of claim 28 wherein the uncured liquid adhesive
melts at a temperature in the range of about 220.degree. F. to
about 260.degree. F.
30. The method of claim 13 wherein the moist ambient air has at
least about forty percent relative humidity.
31. The method of claim 1 wherein the two fabric panels and
adhesive seam together form a bra cup.
32. The method of claim 23 wherein the adhesive is applied onto the
material strip by nozzle coating wherein the bead of adhesive
applied onto the material strip has a thickness that is less than
the thickness of the material strip.
33. The method of claim 7 wherein the adhesive is applied to the
strip of material as the strip of material is applied along the
interface.
34. The method of claim 1 wherein the fabric panels have a first
color and the adhesive, when cured, has a color that substantially
matches the color of the fabric panels.
35. An apparatus for forming an adhesive seam comprising: a fabric
feeder that draws at least two pieces of fabric into abutted
alignment as it moves the fabric through the apparatus; and an
adhesive dispenser that applies adhesive to the two pieces of
fabric in the region of abutted alignment as they are moved through
the apparatus by the fabric feeder.
36. The apparatus of claim 30 wherein the fabric feeder has a top
portion and a bottom portion that together define a nip region into
which the at least two pieces of fabric are drawn.
37. The apparatus of claim 35 wherein the top portion has a belt
feeder and the bottom portion has a knurled roller.
38. The apparatus of claim 35 wherein the top portion and the
bottom portion are knurled rollers and wherein at least one of the
rollers is a driven roller.
39. The apparatus of claim 38 wherein each roller has a roller
surface and the roller surface is selected from the groups
consisting of flat, concave and convex.
40. The apparatus of claim 38 wherein both knurled rollers are
driven.
41. The apparatus of claim 35 wherein the adhesive dispenser is
connected to an adhesive reservoir that stores adhesive in an inert
atmosphere until dispensed.
42. The apparatus of claim 35 wherein the adhesive dispenser has a
material strip conveyor and an adhesive outlet and wherein the
material strip conveyor is aligned with the adhesive outlet such
that a first material strip is conveyed past the adhesive outlet
along its length.
43. The apparatus of claim 42 wherein the adhesive outlet is in
fluid communication with an adhesive container.
44. The apparatus of claim 43 wherein the fabric feeder has at
least one roller which is aligned with the adhesive outlet, wherein
the adhesive outlet is adapted to deposit adhesive on the material
strip as it is conveyed past the adhesive outlet.
45. The apparatus of claim 43 wherein the adhesive container
further comprises a heater.
46. The apparatus of claim 45 wherein the adhesive container
further comprises an adhesive pump sized to pump adhesive from the
adhesive container through the adhesive dispenser orifice.
47. The apparatus of claim 43 wherein the adhesive container is an
air tight container.
48. The apparatus of claim 42 wherein the adhesive outlet is a
nozzle.
49. The apparatus of claim 48 wherein the nozzle is selected from
the group consisting of slot nozzle and spray nozzle.
50. The apparatus of claim 42 wherein the material strip conveyer
cooperates with the fabric feeder to feed the first material strip
that is conveyed past the adhesive outlet into the fabric
feeder.
51. The apparatus of claim 42 wherein the fabric feeder is
configured to press the first material strip into contact with the
at least two pieces of fabric along the region of abutted
alignment.
52. The apparatus of claim 42 further comprising a second material
strip conveyor.
53. The apparatus of claim 52 wherein the fabric feeder receives a
second material strip from the second material strip conveyor and
presses it into contact with the at least two pieces of fabric
along a second region of abutted alignment which is on a side of
the at least two fabric panels opposite the first material
strip.
54. The apparatus of claim 51 wherein the material strip conveyor
has a paper backing conveyor adapted to place a paper strip into
contact with a face of the material strip along its length wherein
the material strip is interposed between the orifice and the paper
backing.
55. The apparatus of claim 53 wherein the material strip conveyor
and the second material strip conveyor each have a paper backing
conveyor adapted to place a paper strip into contact with a face of
the material strip along its length wherein the material strip is
interposed between the orifice and the paper backing.
56. The apparatus of claim 54 wherein the fabric feeder is adapted
to receive the paper strip along with the material strip.
57. The apparatus of claim 55 wherein the fabric feeder is adapted
to receive the paper strip along with the material strip.
58. The apparatus of claim 42 wherein the adhesive dispenser
further comprises a roller coater for transferring adhesive from
the adhesive outlet to the material strip.
59. The apparatus of claim 44 wherein the adhesive dispenser
further comprises a slot nozzle for transferring adhesive from the
adhesive dispenser to the material strip.
60. The apparatus of claim 58 further comprising a doctor blade
positioned adjacent to the surface of the roller coater that
dispenses adhesive onto the material strip.
61. The apparatus of claim 42 further comprising a fluid outlet in
the vicinity of the adhesive outlet.
62. The apparatus of claim 35 further comprising a fabric feeding
surface on which the fabric is placed as it is fed into the fabric
feeder wherein the fabric feeding surface has a sensor that detects
the presence of fabric on the fabric feeder.
63. The apparatus of claim 62 wherein the detector is coupled with
a switch that controls at least one of the fabric feeder and the
adhesive dispenser.
64. The apparatus of claim 35 wherein the fabric feeder further
comprises a guide for feeding the at least two pieces of fabric
into abutted alignment.
65. The apparatus of claim 36 wherein the adhesive dispenser
comprises a nozzle that has an outlet directed at the nip
region.
66. The apparatus of claim 65 wherein the nozzle is selected from
the group consisting of a slot nozzle and a spray nozzle.
67. A curing holder for a fabric article having an adhesive seam
during adhesive cure comprising: a receiving surface with a contour
that substantially mimics the contour of at least a portion of the
adhesive seam of the fabric article.
68. The curing holder of claim 67 wherein the receiving surface is
the exclusive supporting surface for the fabric article during
cure.
69. The curing holder of claim 67 wherein the curing holder is a
bra cup.
70. The curing holder of claim 68 wherein the receiving surface is
configured to reduce the amount of mechanical stress on the seam
compared to a non-contoured supporting surface.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of the filing date of
U.S. Provisional Patent Application No. 60/717,679, filed on Sep.
16, 2005, the disclosure of which is hereby incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to seams for
garments and their manufacture. More particularly, the seams of the
present provide greater comfort to the wearer and are less bulky
than conventional seams, which are formed from multiple plys (e.g.,
layers) of material. The seams of the present invention find
particular advantage in foundation garments (i.e. garments worn
under other garments) especially those over which shear or clingy
outer garments are worn and through which bulky seams are clearly
(and undesirably) visible.
[0003] In a typical garment, a sewn seam is formed between two
fabric panels. Seams are sewn or otherwise formed in a variety of
different ways, depending upon the material, the feature of the
garment formed by the seam and numerous other factors. In a typical
sewn seam, the panels of fabric to be joined by the seams are
superposed at their edges and stitched through at a short distance
from the edges to form two overlapping facing strips at the edge of
the seam. The facing strips are then "plowed" or folded on their
respective panels, and each is stitched flat against the panel.
This seam is formed on the inside of the garment so that the
stitched facing strips are not visible on the outside. In many
garments where the thick seam can lead to chafing or other
discomfort, the plowed strips are then covered with a tape which is
sewn to the panel through the plowed strips. Typically, the edges
of the tape are folded under in order to avoid fraying, before the
tape is sewn to the panels. However, the seam is several plies
thick (even without the tape) and defines a noticeable ridge in the
fabric. This ridge is generally visible and even accentuated when
in foundation garments over which other garments (e.g., shear or
close fitting outer garments) are worn. Also, in foundation
garments that provide shaping and/or support the ridge can cause
discomfort, chafing etc., especially where support and/or shaping
are provided.
[0004] However, sewn seams, despite these disadvantages, are
advantageous and desirable in many classes of garments that provide
support or shape to the wearer. Sewn seams enable the manufacturer
to tailor the garment to provide support or shape in a particular
area (i.e. the area of the seam). Also, the sewn seam enables the
manufacturer to join two types of materials together, or to
configure the fabric panels joined together by the seam to provide
particular support or shape to the wearer.
[0005] One class of garments where the sewn seam finds particular
advantage is brassieres (more commonly referred to as bras). The
bra is a complicated garment from a manufacturing perspective
because it is a garment with cups that define a vaulted three
dimensional shape. Often, these cups are formed from flat panels
that are sewn together. The cup portion is formed with a sewn,
curved seam in the front between two panels. The seam provides an
advantageous element of support for the wearer at this location.
This support is especially advantageous for ample breasted women.
Sewn seams are also advantageous because they allow two different
types of material to be joined together by the seam. Thus, the
manufacturer can join together two materials, each with distinct
characteristics and functions in the garment. For example, again in
the context of a bra cup, a sturdier material that provides support
can be joined with a stretchier material that provides comfort. The
sewn seam provides advantages in other support garments as well.
Sewn seams can be placed in foundation garments at the precise
location where support or particular shape is desired. Thus, from a
support/shape perspective, the sewn seam is very advantageous when
used in foundation garments and active wear.
[0006] However, the sewn seam has fallen from favor from use in
foundation garments and shape wear for purely aesthetic reasons.
Specifically, the visibly detectable seam ridge is extremely
undesirable from a fashion point of view. Consequently, seamless
constructions have been sought for foundation garments and active
wear. While these solutions do address the problem of a highly
visible seam, they are deficient from a support/shaping
perspective. For example, bras have been made with seamless cup
portions comprising a single piece of fabric. This single panel
construction offers virtually no support and cannot be used by a
large segment of the female population (typically those women who
require a large cup bra also require a bra that provides at least
some degree of support).
[0007] Bras with molded cups have been offered as an alternative to
bras with cups having seams. However, manufacture of the molded cup
is labor intensive, since it requires molding the cup to a
particular configuration. This requires the use of many different
molds to approximate the breast size of the wearer. Also, the
process of molding the fabric (typically a heat treatment that
removes the stretch from an elastic material such as spandex) is
time consuming. The molded cup also makes very inefficient use of
fabric, since rather large areas of fabric for the cup and the
strap/stay portion of garment must be reserved for clamping the
cups to the strap/stay portion. These clamped portions are
subsequently removed and discarded, which wastes fabric.
[0008] Consequently, fashionable and manufacturable alternatives to
conventional multi-ply seams that will provide adequate support and
shape for foundations and active wear continue to be sought.
SUMMARY OF THE INVENTION
[0009] The present invention is applicable to seams for many types
of garments. However, it is particularly advantageous in the
manufacture of foundation garments, active wear, shape wear and the
like type of garments (i.e. garments that are configured for fit,
support and/or control). The seams of the present invention present
a smooth surface, compared to prior art multi-ply seams. The smooth
seams are not visually detectable when in a foundation garment over
which close fitting or shear garments are worn. However, unlike
prior art alternatives to multi-ply seams, the seams of the present
invention permit the manufacturer to tailor the garment to provide
support, comfort or shape in addition to providing the highly
desirable smooth appearance. In the context of bras, the present
invention provides particular advantage over the molded bra cup
solution, since the present invention allows for tailoring the bra
cup for fit, comfort and support whereas a molded bra cup cannot be
so tailored. Also, again compared with multi-ply seams, the seams
of the present invention are less likely to irritate or chafe skin
in contact with the seam.
[0010] In accordance with one embodiment of the present invention,
seams are formed of two fabric panels (i.e. a first panel and a
second panel), each panel having a first edge. The first edge of
the first panel abuts, but does not substantially overlap, the
first edge of the second panel. The first and second panels are
joined together by an adhesive. In preferred embodiments, the edges
are connected by a material strip carrying the adhesive. The
adhesive is applied to the material strip in an uncured state.
Preferably, the material strip is placed in contact with the fabric
panels to form the seam while the adhesive is still substantially
uncured. In another preferred embodiment of the present invention,
a seam is formed by applying a first material strip carrying
adhesive on a first major surface at the interface of the two
abutting fabric panels, followed by cure, and then applying a
second material strip carrying adhesive on a second, opposing major
surface at the interface of the two fabric panels (again followed
by cure).
[0011] Although any conventional fabric is contemplated as suitable
for the fabric panels, it is advantageous if the fabric panels are
synthetic materials. Examples of suitable fabrics include synthetic
materials such as polyester, rayon, polyurethane foam, spandex
(e.g., Lycra.RTM. a registered trademark of Invista Technologies
S.A.R.L.), nylon and the like materials and natural fiber materials
such as cotton and wool. As one skilled in the art is aware, fabric
materials typically carry a finish material which gives a material
a particular sheen and/or feel. One skilled in the art is aware
that there are a vast number of finish compositions for fabrics. In
the present invention, a fabric finish is selected that will not
substantially degrade the adhesion between the adhesive and the
fabric panels. One skilled in the art will be able to select an
appropriate finish based upon the particular adhesive used. For
example, if a water-based (i.e. hydrophilic) adhesive is used,
hydrophobic (e.g., non polar) finishes should be avoided.
Silicone-based finishes are examples of those finishes that should
be avoided when a water-based adhesive is used. With certain
adhesives, it may be advantageous to use unfinished fabrics if
possible from an appearance/texture perspective.
[0012] Suitable adhesives are those that wet both the fabric and
the material strip used to join the fabric panels (it is
advantageous, but not required, that the fabric and material strip
be the same material). The adhesive is applied onto the material
strip and placed into contact with the fabric in an uncured state,
and subsequently cured when in contact with the material strip and
fabric panels. It is also advantageous, but not required, for the
adhesive to stretch in its cured state. It is advantageous if the
adhesive will elongate at least one hundred percent (i.e. can
stretch to twice its length in its relaxed state). It is
contemplated that the fabric panels will stretch more than the
adhesive in at least some embodiments.
[0013] Many different adhesives are contemplated as suitable for
forming the seam of the present invention. In one embodiment of the
present invention, thermosetting adhesives are used. As used
herein, thermosetting adhesives are adhesives that cure when
subjected to a thermal cycle of heating followed by cooling.
Another characteristic of thermosetting adhesives is that, once
cured, they cannot be remelted when heated.
[0014] In another embodiment of the present invention,
thermoplastic adhesives are used. Thermoplastic adhesives, much
like thermosetting adhesives, cure when subjected to a thermal
cycle of heating and cooling. However, unlike thermosetting
adhesives, thermoplastic adhesives can be remelted after cure.
[0015] Other adhesives that cure using mechanisms other than a
thermal cure (e.g., ultraviolet radiation cure) are also
contemplated as suitable for use in the present invention. Again,
the requirements are suitable adhesion to fabric and maintaining
adhesion and flexibility over time when subjected to repeated wear
and washing.
[0016] In some applications where the fabric panels are relatively
thick (e.g., 5 mils or thicker and, more typically about 20 mils or
more), such as when the fabric is a fiberfill or urethane material,
adhesive may be applied directly to the abutted edges. A strip of
material is also used to carry additional adhesive to form the
completed seam in these embodiments. Forming a seam from relatively
thick materials in this manner ensures that gaps in the finished
seam will not form.
[0017] In certain preferred embodiments, the seam is formed by
applying to the material strip a heated, thermosetting adhesive in
fluid form. One example of such an adhesive is a polyurethane
adhesive (PUR adhesive) manufactured by the National Starch Co. It
is advantageous if the adhesive contains additives that allow the
seam to stretch along with the fabric panels joined by the seam. A
seam manufactured in accordance with the present invention is
virtually undetectable through clothing, and, when a strip of
material is used, as in a brassiere cup, it provides an element of
support which is adequate for most of the female population.
[0018] Although the adhesive, when introduced into contact with the
material strip, wets the surface of the strip, the amount of
adhesive, the thickness of the adhesive and its viscosity are
selected to ensure that the adhesive does not permeate through the
entire thickness of the material strip. The reason for this is
twofold. If the seam is in contact with the wearer, it is preferred
that the wearer not be in contact with the adhesive used to form
the seam. If the seam is on the exterior of the garment, it is not
desirable for the adhesive to be visible on the surface of the
material strip. The adhesive, if visible through the seam, might
give the garment a stained, soiled or otherwise undesirable
appearance.
[0019] An apparatus for forming an adhesive seam is also
contemplated. The apparatus has a conveyor that grips and draws two
fabric panels into abutting contact. In one embodiment the conveyor
is a dual belt feeder that cooperates with a knurled roller to draw
fabric panels into the nip between the belts and the roller. Both
the belt feeder and roller are provided with driver assemblies that
impart the desired circular motion to the belts and cause the belt
and rollers to draw the fabric panels into the nip thereof. The
apparatus is also equipped with a feeding mechanism that feeds the
strip of material from a roll or other mechanism that is suitable
to support and dispense such material. As the strip of material is
fed from the dispensing mechanism, adhesive is applied to the strip
of material. The adhesive is applied using mechanisms such as a
spray nozzle, a slot nozzle or a roller coater. The adhesive is
applied to the material in a substantially uncured form.
[0020] In another embodiment, at least one of the rollers forming
the nip into which the fabric is fed and drawn is knurled. At least
one of the rollers is driven and it is advantageous if both rollers
are both driven and knurled. It is advantageous if the rollers have
the same size and move at the same speed, as such an arrangement
provides an even seam.
[0021] The roller surfaces can be either flat, concave or convex.
It is advantageous if at least one of the roller surfaces is
convex, as this surface configuration draws the fabric into and
through the nip efficiently.
[0022] The apparatus feeds the strip of material carrying the
adhesive into contact with the fabric panels in abutting contact
such that the strip of material is placed in contact with both
panels and bridges the region where the two panels are brought
together along substantially the entire length of that region.
Bringing the strip of material into contact with the fabric panels
in this manner, the apparatus forms a seam joining the first panel
and the second panel.
[0023] In an advantageous embodiment, the strip of material is
backed with paper, such that the paper backing is interposed
between the strip of material and the roller. Among other
advantages, the paper prevents adhesive, placed on the strip of
material to promote adhesion between it and the fabric, from coming
into contact with the rollers. After the strip of material is
placed into contact with the fabric panels and begins to cure, the
paper backing is removed from the strip of material.
[0024] After the seam is formed, the adhesive is at least partially
cured so that the seam will hold the panels together when the
assembled panels are removed from the apparatus for subsequent
processing. The apparatus has a curing station that facilitates at
least partial cure of the adhesive. The curing conditions depend
upon the adhesive that is used. For example, thermosetting resins
are heated to render them sufficiently viscous for application onto
the material strip. Generally, the adhesive is more viscous (i.e.
has a greater resistance to flow) at lower temperatures. At lower
temperatures, the adhesive is applied onto the strip of material
with a greater bead thickness. Generally, a temperature is selected
that will ensure a certain minimum degree of tackiness between the
panels themselves or between the panels and the strip of material
used to join the panels together.
[0025] Such adhesives are cured by subjecting them to cool, moist
air. Thus, the curing section for an apparatus in which a
thermosetting resin is used to assemble the seam will introduce
cool, moist air proximate to the assembled seam in order to at
least partially cure the adhesive. It is advantageous if the
assembled seam is placed on a surface with a contour that somewhat
mimics that of the finished seam. Placing the seam on such a
surface will prevent the fabric panels from bunching, pulling,
etc., which could place the partially cured seam under undue
stress. Such stress could cause undesired imperfections in the
fully cured seam (e.g., gaps, irregular appearance, etc.). Curing
on an appropriately contoured surface ensures that the seam will
not be subjected to undue mechanical stress during cure.
Appropriate curing conditions depend upon a number of different
factors among them being: 1) the temperature of the adhesive when
applied to the seam; 2) the thickness of the bead of adhesive that
is deposited to form the seam; 3) the amount of moisture in the
air; 4) the temperature of the air; and 5) the volume of air
circulating past the seam as it is cured.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The foregoing brief description, as well as further objects,
features, and advantages of the present invention will be
understood more completely from the following detailed description
of presently preferred, but nonetheless illustrative embodiments in
accordance with the present invention, with reference being had to
the accompanying drawings in which:
[0027] FIGS. 1A-1C are schematic diagrams representing a presently
preferred process for manufacturing a garment seam in accordance
with one embodiment of the present invention;
[0028] FIG. 2 illustrates an alternate embodiment of a garment seam
in accordance with the present invention, useful on portions of a
garment made of fiberfill or urethane;
[0029] FIGS. 3A and 3B illustrate an alternate method for the
manufacture of a brassier cup using a darted seam in accordance
with one embodiment of the present invention;
[0030] FIG. 4 illustrates a support bra structure according to one
embodiment of the present invention;
[0031] FIG. 5 illustrates a support bra structure according to a
second embodiment of the present invention;
[0032] FIG. 6 is a perspective view of the top belt assembly and
bottom roller assembly for one embodiment of the apparatus of the
present invention;
[0033] FIG. 7 is a perspective view of the top belt assembly
illustrated in FIG. 6;
[0034] FIG. 8 is a perspective view of the nip region of the
assembly illustrated in FIG. 6 adjacent the bottom roller
assembly;
[0035] FIG. 8A is a perspective view of another embodiment of the
assembly illustrated in FIG. 6 in which the top belt assembly is
replaced by a driven knurled roller;
[0036] FIGS. 9A-B illustrate the top belt assembly illustrated in
FIGS. 6-8 in both its belt up (FIG. 9A) and belt down (FIG. 9B)
positions;
[0037] FIG. 10 is a top view of a top belt assembly of the present
invention feeding fabric into the apparatus;
[0038] FIG. 11 is another embodiment of the top belt assembly
illustrated in FIG. 10 but with a divider between fabric panels as
they are fed into the top belt assembly;
[0039] FIG. 12 is a detail view of a spray nozzle suited for use in
one embodiment of the apparatus of the present invention;
[0040] FIG. 13 is a detail view of a slot nozzle suited for use in
one embodiment of the apparatus of the present invention;
[0041] FIGS. 14A-14C are schematic diagrams of a roller coater
suited for use in one embodiment of the apparatus of the present
invention with 14A a top plan view, 14B a top plan view with
underlying components in phantom and 14C a cut away side view;
[0042] FIG. 15 is a side view of an adhesive dispenser for use in
one embodiment of the present invention;
[0043] FIG. 16 is a plan view of the midsection of the adhesive
dispenser illustrated in FIG. 15;
[0044] FIG. 17 is a perspective view of the top section of the
adhesive dispenser illustrated in FIG. 15; and
[0045] FIG. 18 is a perspective view of a contoured surface on
which bra cups can be placed while the adhesive seam is cured.
DETAILED DESCRIPTION
[0046] Referring to the drawings, FIGS. 1A-1C are a schematic
representation of seams according to certain embodiments of the
present invention. FIG. 1A illustrates two panels or sheets of
fabric 10, 12 in edge-wise abutment at 13, in preparation for
forming a seam. The fabric panels are preferably made of a
synthetic material such as polyester, polyurethane, nylon, rayon,
etc. It is advantageous if the fabric panels are smooth before the
seam is formed. If the material is not sufficiently smooth, it can
be calendared. Calendared materials provide a more uniform surface
on which to apply the material strip carrying adhesive. This
ensures that the adhesive contact is uniform, and the seam is less
likely to bunch when formed than if the fabric is
non-calendared.
[0047] The fabric panels 10, 12 are typically finished fabrics,
although the fabric panels can also be unfinished. Finished fabrics
are well known to those skilled in the art. There are many fabric
finishes, each providing a certain feel and appearance to a fabric.
If finished, the fabric finish must be compatible with the adhesive
that is used to form the seam. In the context of the present
invention, compatible means that the adhesive will adhere to the
fabric with the finish thereon. One skilled in the art can readily
ascertain how to select a finish that is suitable for use with a
particular adhesive, and vice-versa. For example, if a water-based
(i.e. hydrophilic/polar) adhesive is used, then the finish should
not be hydrophobic or non-polar. Silicone-based finishes are
examples of finishes that are not suitable for forming an adhesive
seam using a water-based adhesive. If a fabric has a finish to
which the adhesive will not suitably adhere, the problem may be
addressed by spray washing the fabric to remove or modify the
finish. Finish properties can also be modified (e.g., the finish
texture can be roughened) by subjecting the fabric to an electric
field. One skilled in the art is well versed in the materials and
conditions required to remove/modify a fabric finish, and, as such,
they will not be discussed in detail herein.
[0048] The fabric panels 10, 12 are illustrated as rectangular, but
can be cut to any desired shape or size. One skilled in the art is
aware of the many different techniques used to cut fabric panels
for use in garment manufacture. Such techniques include Gerber
cutting, die cutting and laser cutting. It is advantageous if the
fabric panels are cut using the more precise techniques of laser
cutting, sonic cutting or die cutting. Laser cutting, sonic
cutting, hydro cutting and die cutting provide fabric panels with
smoother, more uniform edges compared with other conventional
techniques for cutting fabric (e.g., Gerber cutting). It is easier
to abut fabric panels with smooth, uniform edges, and panels with
such edges are less likely to bunch or otherwise deform in a manner
that might result in a non-uniform seam. In this regard, seam
imperfections (e.g., dents or holes at the seam edge) may not
adversely affect the mechanical integrity of the seam. However,
such imperfections may not be acceptable from an appearance
perspective. In a preferred embodiment of the present invention,
the fabric panels are cut from the fabric using laser cutting,
hydro cutting or sonic cutting. Although applicants do not wish to
be held to a particular theory, it is applicants' belief that laser
cutting and sonic cutting are more accurate and therefore provide
for a more consistent and uniform cut. This ensures greater
conformity of the edges of the two fabric panel that are brought
together in abutted alignment. Also, applicants also believe that
laser cutting and die cutting fuse, at least somewhat, the fibers
at the cut edge of the fabric panels. This also allows the fabric
panels to be fitted together more precisely, providing for a
smoother seam that is less visible under clothing.
[0049] The material and thickness of the fabric panels is largely a
matter of design choice. While there is no requirement that the
fabric panels be the same material, there are certain constraints
when different materials are used. One constraint is the finish on
the materials. While there is no requirement that the materials
have the same finish, the finishes should permit a comparable
degree of adhesion between the panel and the adhesive. In this
regard, one panel should not have a hydrophilic finish when the
other has a hydrophobic finish, for example. Another constraint is
thickness. While there is no requirement that the fabric panels be
of identical thickness, it is advantageous if they are of similar
thicknesses. A substantial difference in thickness between the two
panels (e.g., one panel is more than fifty percent thicker than the
other panel) will result in an uneven seam that is more likely to
be visible through shear or clingy garments worn over any such seam
compared to a seam formed from two panels of substantially equal
thickness.
[0050] In FIG. 1B, an elongated strip of material, preferably a
length of material 14 is wetted with a liquid adhesive material 16.
For purposes of this illustration, the adhesive is depicted as
being sprayed onto the material. However, there are many different
ways in which the adhesive can be applied to the material in a more
controlled manner (e.g., slot nozzle or roller coater). The
mechanisms for applying the adhesive are discussed in greater
detail below.
[0051] The piece of material used to join together the two fabric
panels is referred to herein as a strip. While the term strip
typically connotes a long and narrow configuration, the term strip,
as used herein, is meant to include a piece of material of any
suitable configuration. The strip of material is also of any
suitable thickness. While any thickness is contemplated, it is
advantageous if the thickness of the material strip is less than
the thickness of the fabric panels. Thicker strips, while
contemplated, are contrary to the objectives of the present
invention, which is to provide a less noticeable seam. In preferred
embodiments, the strip of material is thicker than the adhesive
applied thereon. This ensures that the adhesive will not wet
through the strip of material. Examples of suitable thicknesses for
the material strip are in the range of about 1 mil (a mil is 1/1000
of an inch) to about 7 mils thick.
[0052] The weave of the strip is selected to prevent adhesive from
penetrating through the thickness of the strip. As previously
noted, this prevents the adhesive from being visible on the surface
of the material strip, resulting in an undesirable appearance. This
also prevents adhesive from penetrating through the material strip
on the underside of the seam, which would result in adhesive being
adjacent the skin of the wearer. This could result in skin
irritation or other discomfort to the wearer. Again, the objective
is to prevent the adhesive from penetrating through the thickness
of the strip. Again, this is a feature that provides a seam with an
advantageous appearance and is not required to ensure the
mechanical integrity of the seam.
[0053] Various materials and material thicknesses may be selected
for the elongated strip of material, depending on the application.
Typically the material will be the same as or similar to the panel
material, although this is not required. If the material is
finished, the finish must not inhibit the adherence of the
adhesive, as described above. The thickness of the material strip
is largely a matter of design choice, and will be governed largely
by the desired appearance of the seam. For example, strips having a
thickness that will show through outerwear are less desirable. The
one requirement is that the strip of material be at least as thick,
and preferably thicker, than the adhesive applied to and carried by
the strip of material. In one embodiment, the material is a tricot
knit fabric material having a thickness of about 1 mil to about 7
mils and a width in the range of about 3/32'' to about 1/4''.
However, those skilled in the art will appreciate that strips made
of many different materials and with many different sizes may be
used.
[0054] The width of the strip of fabric material is also a matter
of design choice. Typically, the strip of fabric material will have
a width of about 0.25 inches to about 0.75 inches. However, widths
outside this range are contemplated.
[0055] As noted above, it is advantageous if the strip of fabric
material does not have an open weave that will allow the adhesive
to penetrate through the thickness of the strip of material.
However, it is advantageous if the strip of material does stretch
at least somewhat in both the length and width directions. This
provides the seam with a bit of give, which adds some additional
adjustability and thus comfort for the wearer. However, although
desirable, the degree of stretch in the width direction should
never be such that gaps form in the seam due to the degree of
stretch provided by the strip of fabric material.
[0056] One skilled in the art is aware that degree to which fabrics
stretch is almost unlimited. Some fabrics have a weave and material
that provides for very little (i.e. almost zero percent) stretch.
In the context of the present invention, the percent to which a
fabric stretches is the difference in the dimension of the fabric
in the direction of the stretching force compared to that dimension
when the fabric is in its relaxed state (i.e. no stretching force
applied) as a percent of the dimension of the fabric in its relaxed
state. As one skilled in the art is aware, fabrics stretch up to
two hundred (200) percent or even higher.
[0057] Thus, except for the constraints on open weave stated above,
the seam of the present invention can be formed using a material
strip and fabric panels with any degree of stretch (including zero
degrees). Certain considerations might inform the selection of a
particular degree of stretch, chief among them being the need to
avoid a seam that will stretch to form gaps between the panels.
This consideration creates a greater degree of tolerance for
stretch in the length direction than in the width direction. Also,
since in certain embodiments, the adhesive also stretches up to one
hundred percent, one will typically select fabric panels, material
strip and adhesives with a commensurate degree of stretch.
[0058] As noted above, many different adhesives are contemplated as
suitable. The selected adhesive will adequately adhere to the
fabric panels forming the seam and the finish on such panels.
Furthermore the adhesive, once cured, must remain supple over time
even through repeated wearings and washings of the garment.
Examples of suitable adhesives include thermosetting adhesives and
thermoplastic adhesives. One example of a thermoplastic adhesive is
Griltex.RTM. copolyester adhesive. Thermoplastic adhesives are
contemplated as useful for forming a seam when the fabric panels
are knitted or woven fabric. In one embodiment, it is advantageous
if the adhesive contains a dye so that is at least somewhat matches
the color of the fabric panels and/or the material strip. Dyes or
other additives suitable for coloring adhesive are well known in
the art and not described in detail herein. The color of the
selected dye depends upon, for example, the color of the fabric
panels and the material strip and the degree of match between the
adhesive and the fabric panel/material strip that is sought. Also,
the dye or other color additive must be chemically compatible with
the adhesive. For example, if the adhesive is water-based, then the
dye would also be water-based. Conversely, if the adhesive is
hydrophobic, then the dye would also be hydrophobic.
[0059] One example of a thermosetting adhesive is a polyurethane
based adhesive such as PUR from National Starch Inc. In order to
provide an adhesive with sufficient stretch when cured, additives
can be included with the adhesive. One skilled in the art is aware
of suitable additives for thermosetting adhesives that increase the
stretch in the cured adhesive. In certain preferred embodiments,
the adhesive is one that cures when cooled, and the cure is
accelerated in a moist air environment.
[0060] In the embodiment of the present invention in which a
thermosetting adhesive is used, the adhesive is heated in a
container under pressure. An inert atmosphere is provided to
pressurize the adhesive. In one embodiment, the inert atmosphere is
an argon atmosphere. In another embodiment, the inert atmosphere is
super-dried air. Nitrogen is yet another example of an inert
atmosphere. In the context of dispensing adhesive, an inert
atmosphere is one in which the adhesive does not substantially
cure. The adhesive is dispensed either by pressure from the inert
atmosphere alone or by use of a mechanical pump. The adhesive
material is dispensed in liquid form. In the embodiment where
pressurized argon is used to dispense the adhesive, approximately
five pounds of argon pressure is all that is required to accomplish
this objective. The material cures when cooled in ambient air and
the cure is accelerated if the air is moist. The greater the amount
of moisture in the air, the faster the cure. The preferred adhesive
is a thick paste that is heated to be converted to a liquid form.
The melting temperature will depend upon the particular adhesive
used. Specifically an adhesive with a melting temperature that is
less than the temperature that would adversely affect the fabric
panels being attached with the seam is preferred. For example, if
fabric panels will be adversely affected by temperatures higher
than 350.degree. F., adhesives with a melting temperature higher
than about 350.degree. F. should be avoided. Similarly, if the
fabric can withstand temperatures of about 300.degree. F. or less,
then and adhesive with a melting temperature of less than about
300.degree. F. should be used.
[0061] Adhesives that require temperatures of greater than
350.degree. F. to be in liquid form are less preferred because the
synthetic materials used for the strip of material and fabric
panels might be damaged if placed into contact with a substance at
such higher temperatures. Also, high temperatures are preferably
avoided for operator safety. It is advantageous if the uncured
adhesive melts at temperatures in the range of about 220.degree. F.
to about 280.degree. F., and more preferably temperatures of about
220.degree. F. to about 260.degree. F. and is sufficiently liquid
(i.e. have a viscosity that is sufficiently low) at these
temperatures to facilitate application onto the strip of material.
In this regard, adhesives with curing temperatures in the lower
half of the aforesaid range have a tackiness when the adhesive is
applied to the strip that provides for advantageous handling of the
seam prior to cure. In any event, overheating is to be avoided as
it can cause the adhesive to discolor (e.g., turn yellow). This can
cause a less than desirable appearance.
[0062] In this regard, it is also advantageous if the fabric itself
is heated when the seam is formed. Heated fabric is less prone to
wrinkle, and a smooth seam will more likely result with the fabric
is heated. Again the upper limit on temperature is the heat
tolerance of the fabric itself. There is no need to heat the fabric
to a temperature in excess of the melting temperature of the
adhesive.
[0063] The adhesive is applied using any suitable mechanism. A
roller coater provides uniformity and controlled application, but
other mechanisms such as a slot nozzle or a spray nozzle are also
contemplated as suitable. A slot nozzle provides a bead of adhesive
and therefore permits the application of adhesive directly onto the
strip at a controlled thickness. A spray nozzle permits a large
amount of adhesive to be applied quickly but the amount of
"overspray" onto other surfaces is greater with a spray nozzle than
with a slot nozzle or roller coater. Those skilled in the art will
appreciate that adhesive may be applied by any other conventional
method that will allow it to wet the strip of material 14.
Application conditions (e.g., adhesive thickness) are controlled to
prevent the adhesive from bleeding through the strip of material.
For example, if the strip of material is about 7 mils thick, the
adhesive is applied using conditions (e.g., thickness, viscosity,
etc.) that limit the penetration of the adhesive into the strip of
material to about 5 mils or less.
[0064] In FIG. 1C, the strip of material 14 now carrying the liquid
adhesive 16 is placed over the region of edge-wise abutment 13,
thereby forming an adhesive seam 15. FIG. 1C shows the strip of
material 14, after it has received the adhesive 16, applied over
the abutted joint 13 between the fabric sheets 10, 12. It is not
required to apply pressure to the strip of material 14 during
initial cure but only to hold the panels 10 and 12 stationary. The
preferred adhesive cures if exposed to an ambient atmosphere, but
curing can be accelerated by exposing it to moist (i.e. humid)
and/or cold air. One example of suitably moist air is ambient air
with at least about forty percent humidity. In embodiments
described in detail below, once the strip of material 14 is in
position, a stream 18 of cool, moist air is directed at the strip
of material 14. This initiates curing of the adhesive, whereupon
the tape and the edges of the sheets 10, 12 are retained together
by the adhesive to form a seam 15. This permits the fabric seam to
be handled without separating the seam.
[0065] As previously noted, it is advantageous if the fabric seam
is placed on a surface with a contour that mimics the contour of
the fabric article. Such an arrangement avoids mechanical stress on
the seam as it cures.
[0066] Although the seam depicted in FIG. 1C illustrates the strip
of material on one surface of the fabric panels 10 and 12. It is
contemplated that the strip of material 14 will be adhered to the
opposing surface of panels 10 and 12 to form a two-sided seam. In
these embodiments, once the first strip of material 14 is applied
to join together panels 10 and 12, the seam assembly is turned over
and a second strip of material (not shown) is applied on the
opposing side.
[0067] Adhesive-backed strips have been used in garment manufacture
for either garment hems or elastic edges. The adhesive strips used
for these purposes are not suited for making seams, especially
seams with corners or curves such as the seams found in bra cups.
The adhesive-back strips are supplied with the adhesive pre-applied
on the strip (i.e. well in advance (e.g., at least hours, more
likely days and typically weeks) of using the strip to make the
garment) and partially cured. The adhesive is therefore in a solid
state and the strips must be reheated when the strip is applied to
the seam. Solid adhesive is less preferable to the adhesive applied
in liquid form, as described herein. In the present invention, the
liquid adhesive is applied to the material strip only moments
before the seam is formed. Corner and curved seams are readily
formed using the material strip carrying liquid adhesive as
described herein.
[0068] One advantage of the present invention is that, since the
panels 10 and 12 are in abutted alignment for seam formation, the
need for a seam allowance is avoided. A sewn seam needs to have a
seam allowance (i.e. extra material) where the panel edges are sewn
together. Thus a portion of each panel extends beyond the sewn
seam. This extended edge portion is plowed open and sewn as
discussed above. The extended edge portion serves no purpose in the
garment (it is typically in the inside of the garment, hidden from
view). In the present invention, there is no need for a seam
allowance, since the edges are abutted and the adhesive seam is
formed at the abutment of the two edges. The panels do not extend
beyond the abutted region. Therefore, the fabric panels can be cut
to the exact size that is required for the garment, without the
need for a seam allowance. Thus, the present invention provides a
significant saving of material by avoiding the need for a seam
allowance.
[0069] The present invention provides particular advantage in the
manufacture of bra cups. In the manufacture of bra cups, a
substantial amount of manual labor is required. This is especially
true in the case of molded cups that require time and labor to
shape into different sizes. In addition, in prior art methods for
bra manufacture, the fabric must be cut oversized in order to
provide clamping areas, which eventually become waste material.
Accordingly, the seams of the present invention will save a
substantial amount of material when used to manufacture bras. In
addition, those skilled in the art will appreciate that the process
for forming the adhesive seams described generally above is capable
of being automated. Using an automated process for bra manufacture
also provides significant advantages over prior art techniques for
making bras which are more highly customized and therefore more
labor intensive.
[0070] Various modifications to the process described above are
contemplated, and those skilled in the art will appreciate that
modifications in addition to those describe herein are possible
without departing from the scope and spirit of the invention. For
example, adhesive might be applied to the fabric panels rather than
the strip of material. Alternately, tape (i.e. a strip of material
already carrying an adhesive) could be provided, for example, in
rolls. The tape is then heated to liquefy the adhesive prior to
applying the tape to the seam. In yet another modification, the
heat may be applied after the tape is placed into contact with the
fabric panels. This allows the seam to be formed in one quick
operation. Also, the panels can be lightly stitched together (i.e.
basted) either before or after the adhesive seam is formed for
additional seam integrity. Since the objective of the present
invention is to provide a less visible, more comfortable seam it is
preferable that the material strip carrying adhesive be applied
over any such stitching.
[0071] In yet another embodiment, the strip of material is applied
with a paper backing. Once adhesive is applied to the front side of
the strip of material, and the strip of material is placed into
contact with the fabric panels to form the seam, the paper backing
is removed from the strip of material.
[0072] FIG. 2 is an alternate embodiment of a fabric seam formed in
accordance with the present invention. In this case, the panels 10'
and 12' are relatively thick sheets of material (e.g., thicknesses
greater than about 1/16'' and up to about one inch or more).
Examples of these thicker materials include fiberfill, urethane,
foam and the like materials. Such materials are commonly used for
bra cups. In this case, the adhesive 16' is provided between the
abutted edges defining the seam, to retain them. The embodiment of
the seam in FIG. 2 can be reinforced by applying a material strip
carrying adhesive (not shown) over the abutted faces of panels 10'
and 12'.
[0073] FIGS. 3A and 3B illustrate an alternate construction and
manufacturing process for a bra cup. In this case, the fabric panel
10'' is formed with a triangular cut-out or "dart" 20. As shown in
FIG. 3B, the cup is assembled by bringing the edges forming the
dart 20 into abutment and covering the abutting edges with a
material strip 14' carrying adhesive in the manner already
described. If the fabric 10'' is fiberfill, urethane or the like,
the edges of the dart 20 could be secured together with adhesive,
as illustrated in FIG. 2. This would result in the formation of a
perfectly smooth cup, without the need for molding.
[0074] FIG. 4 illustrates a bra 100 with a supporting cup structure
110. This cup material is urethane foam. Generally rectangular
upper panel 112 and two roughly triangular lower panels 114 and 116
are joined together in a "T" pattern. A material strip 120 is
adhered to the fabric panels in the seam region. The material strip
120 reinforces the seam, making it stronger, and providing enhanced
support.
[0075] FIG. 5 illustrates a further support bra cup structure 130.
Structures made from left and right urethane foam panels 131, 132.
In this case, the single strip of material 134 is shown
schematically in FIGS. 1A-1C. However, it will be appreciated that
it could also be manufactured with two strips of material one on
each major surface of panels 131 and 132. Since the panels 131 and
132 are thicker urethane material, adhesive can be introduced onto
the abutted edges of the foam panels 131, 132. This adhesive is in
addition to, and not in place of, the adhesive carried by the strip
of material 134.
[0076] Referring to FIG. 6, there is illustrated an apparatus 200
for abutting two panels of material (not shown) and placing the
abutted panels into contact with a strip of material carrying
adhesive. The apparatus 200 feeds the two panels of material and
the strip of material through the apparatus so that the strip of
material forms a seam over the butted portions of the panels.
[0077] The apparatus 200 has a top belt assembly 210 and a bottom
roller assembly 220. The top belt assembly is configured to feed
two fabric panels (not shown) into abutting contact with each other
when fed into the nip 201 defined by the top belt assembly 210 and
bottom roller assembly 220. Roller 222 is mounted on a slant post
221 which allows the panels of material to naturally curve as they
pass through the nip region 201 defined by top belt assembly 210
and roller 220.
[0078] FIG. 7 is a detail view of the top belt assembly 210. The
top belt assembly has two belts, a right belt 211 and a left belt
212. Both are driven by roller 215. Each belt is used to feed a
garment panel (not shown) into abutting contact with another
garment panel and maintain the abutting contact while the strip of
material supporting the adhesive is applied thereto. In the
embodiment of the present invention where the garment is a bra cup,
the two panels of the cup are fed into the top assembly. One panel
is gripped and advanced into the apparatus 200 by right belt 211,
the other panel being gripped and advanced by left belt 212. The
tension in each belt 211, 212 is independently controlled by
respective right 213 and left 214 lift cylinders. This is
particularly advantageous in those embodiments where the first and
second fabric panels have different thicknesses. The movement of
the right and left belts 211, 212 is controlled by stepper motor
(not shown) via shaft 215.
[0079] FIG. 8 is a detail view of the top belt assembly 210 and the
bottom roller assembly 220. A piece of fabric 235 supported by
table 230 is in the background. As illustrated in FIG. 8 material
235 has been fed through the nip region 240 between top belt
assembly 210 and bottom roller assembly 220. The roller assembly
220 is on a slanted, post-type support 221, allowing contoured
garment panels to naturally curve through the nip region 240. This
avoids undue stress being placed upon the newly formed seam, and
makes it less likely that the seam will be forced apart before the
adhesive is cured.
[0080] An alternate configuration of the assembly 200 illustrated
in FIG. 6 is illustrated in FIG. 8A. In FIG. 8A, the nip region 201
has a directly driven top roller 213 instead of the dual belt
assembly illustrated in FIG. 8. The top roller 213 is knurled, as
is bottom roller 222. In this embodiment, top paper 214 is fed over
top roller 213 and into nip region 201. Bottom paper 216 is fed
under bottom roller 222 and into nip region 201. As the fabric
panels (not shown) are fed into the nip region 201, and
adhesive/adhesive strip (also not shown) is applied thereto, the
paper 214, 216 are placed on the back of the seam so formed. This
prevents glue that is used to form the seam from getting on the
rollers 213, 222. As previously discussed, the paper backing 214,
216 is easily removed from the seam after the fabric panels are
removed from apparatus 200 but prior to complete adhesive cure.
[0081] Many different types of paper are contemplated as suitable.
In one embodiment, standard craft paper (i.e. paper with a
thickness of 5/7000'' (7.143.times.10.sup.-4 inches)) is
contemplated as suitable. The thickness is selected so that the
craft paper can act as an effective barrier between the glue
dispensed onto the fabric strip and the rollers, 213 and 222. In
this regard, it is advantageous if the width of the paper backing
is approximately equal to the width of the rollers.
[0082] The top belt assembly 210 is equipped with a front belt
lifting unit illustrated in FIGS. 9A-9B. Referring to FIG. 9A, the
lifting assembly 250 is pivotally mounted on main belt support 255.
Tension rods 251, 252, pull back on lifting assembly 250, thereby
causing the front portion of belts 211, 212 to lift above table
230. Note that only the front portion of belts 211, 212 is so
lifted. Belt support 255 keeps the belts 211, 212 in contact with
bottom roller 222 (FIG. 8). Again, in the context of bra
manufacture, lifting assembly 250 allows an operator to join two
cup panels and to insert a second set of cup panels immediately
following. Such a continuous feeding mechanism avoids uncured
adhesive from depositing on the roller and belt assemblies.
Referring to FIG. 9B, once the garment panels have been fed into
the belt assembly 210, the lifting assembly 250 is pivoted down to
better grip and advance the garment panels.
[0083] Referring to FIG. 10, the top belt assembly 210 is
illustrated advancing garment panels 235', 235'' therethrough.
Garment panels 235', 235'' are advanced through the nip between the
top belt assembly 210 and the bottom roller assembly (not shown) to
form the seam therebetween. In FIG. 10, the lifting assembly 250 is
in its up position and ready to receive another garment panel.
[0084] In the embodiment illustrated in FIG. 10 a reflective
surface portion 265 is placed on the work table 230. The reflective
surface is placed in the path of the advancing garment panel, which
is indicated by arrow 260. An optical sensing assembly 270 is
provided to sense a break in the feed of garment panels. The
optical sensing assembly is equipped with a photosensor head 271
that emits a signal directed toward reflective surface 265. When
garment panels are passing over reflective surface 265, any signal
that is reflected back to photosensor head 271 is weak. However, if
there is a break or gap in the advancing garment panels such that
reflective surface 265 is uncovered, then the signal reflected back
to photosensor head 271 is stronger. This stronger signal is
transmitted via optical fiber 272 to optical sensing assembly 270.
Sensing a break in the garment material, the optical assembly sends
a signal back to the apparatus to stop the movement of the belts
211, 212.
[0085] Referring to FIG. 11, the work plate 230 is configured with
divider 280. The divider 280 serves to guide garment panels 235'
and 235'' into abutted alignment. The guide works by ensuring that
garment panel 235' is guided/advanced by belt 211 and garment panel
235'' is guided/advanced by belt 212. Garment panels 235' and 235''
are two halves that will be joined together to form a bra cup.
[0086] As previously noted, the liquid adhesive is dispensed onto
the strip of material using a variety of different dispensing
mechanisms. A spray nozzle 300 suited for spraying liquid adhesive
onto the strip of material is illustrated in FIG. 12. The nozzle
300 has an adhesive inlet 310 and an air inlet 320 for forcing the
adhesive through nozzle 340. The nozzle assembly 300 is also
equipped with a needle valve 350. The needle valve 350 is adjusted
using the adjustment screw 351 to control the force, spray volume
and area of the adhesive dispensed by nozzle end 340. In order to
avoid clogging nozzle end 340 with cured adhesive once the nozzle
is turned of, needle valve 350 is configured to project through
nozzle 340 when turned off, thereby forcing all of the adhesive out
of nozzle 340.
[0087] Another embodiment of a liquid adhesive dispensing mechanism
is illustrated in FIG. 13. FIG. 13 illustrates a slot nozzle 400.
The slot nozzle 400 has a slot 401 that is placed proximate roller
222 of bottom roller assembly 220. Hose 405 delivers adhesive to
slot nozzle 400. The strip of material (not shown) is conveyed by
roller 222 past slot nozzle 400, where liquid adhesive is dispensed
thereon. The strip of material is then advanced into the nip 240
between bottom roller assembly 220 and top belt assembly 210. In
the nip region 240 the material strip carrying adhesive is placed
into contact with abutting garment panels (also not shown) fed into
the nip 240 by the top belt assembly 210. Optionally, paper backing
(FIG. 8A) is also fed through nip region 240 in a manner such that
the paper backing is interposed between the strip of material and
the roller 222/belts 211, 212.
[0088] Yet another embodiment of a liquid adhesive dispensing
mechanism is illustrated in FIGS. 14A-C FIG. 14A is a top view of
guide assembly 501 of roller coater 500 (FIG. 14B) and illustrating
top roller 514, coating roller 510 and material guide roller 520.
Material guide roller 520 and material guide 521 cooperate to feed
the material to be coated (not shown) to the nip between top roller
514 and coating roller 510. Material guide 521 is adjustable to
accommodate material with a variety of thicknesses. Coating roller
510 is similarly adjustable, or can be changed out so that the
roller width and material width are comparable. It is advantageous
if the roller coater is adjustable to accommodate material strips
up to at least one inch in thickness. The goal is to control the
amount of excess adhesive (i.e., adhesive dispensed from the roller
coater but not applied onto the strip of material). Referring to
FIG. 14C a side view illustrates coating roller 510 receiving
adhesive 512 from supply roller 530 that has a surface 531 that
receives adhesive from reservoir 540. The strip of material is fed
through the nip 514 between top roller 514 and coating roller 510.
Referring to FIG. 14B, the roller coater 500 is also equipped with
an eccentric cam 550. Eccentric cam 550 is used to adjust the
position of adhesive doctor blade 551 (FIG. 14C). Adhesive doctor
blade 551 removes excess adhesive 512 from coating roller 510. The
excess adhesive 551 removed from coating roller 510 flows downward
back into reservoir 540.
[0089] The material guide 521 is adjusted to ensure that the
material is guided into place for proper feeding into the nip 514
between top roller 511 and coating roller 510. One feature of
material guide 521 is air cylinder 522. Air cylinder 522 is used to
lift material guide 521 to remove the material strip (not shown)
from contact with the adhesive roller. This is useful when the
apparatus is about to be stopped and one does not wish to add
adhesive to the remaining material as the final portion of the
material strip carrying adhesive is advanced toward the last set of
fabric panels before the apparatus is turned off. Other aspects of
the material guide 521 are not shown in detail but are readily
understood and implemented by one skilled in the art. These
features include adjustable sides to guide 521 to accommodate
material strips in a variety of widths.
[0090] Typically, the rotating speed of the top and bottom rollers
is adjusted to control the rate at which the fabric/strip of
material/paper is fed into the nip of the apparatus. However, the
roller coater is optionally equipped with a stepper motor (not
shown). The stepper motor controls the speed at which the strip of
material carrying adhesive is dispensed from the roller coater.
This speed needs to be compatible with the speed at which the
panels are fed into abutting alignment by the apparatus, to ensure
that the seam is formed as the panels are fed through the
apparatus.
[0091] As noted above, one type of adhesive that is contemplated
for use in the present invention is a thermoset adhesive that cures
permanently when subjected to heat and subsequently cooled. In the
context of the present invention, a permanent cure is one where the
adhesive, once cured, will not remelt when subjected to elevated
temperatures post cure. Typically the cure of such adhesives is
accelerated when the adhesive is exposed to moist air. The greater
the amount of moisture, the faster the cure. The cure is
accelerated if the moist air is cooler (i.e. room temperature or
below). While one skilled in the art can design a number of
different apparatus that are configured to handle and dispense such
adhesives, the following apparatus is one example of such an
apparatus. This apparatus is more completely described in U.S.
patent application Ser. No. 11/186,061, filed Jul. 22, 2005 and
entitled "Method of Garment Manufacturing Method Using
Thermosetting Adhesively-Attached Seams" and incorporated by
reference herein.
[0092] The exemplary apparatus 600 is illustrated in FIG. 15.
Apparatus 600 has two sections, 610 and 620. Section 610 receives a
container of adhesive. Section 610 is also equipped with heat
jacket 612 for heating the adhesive within container 611. Section
620 has a reservoir 621 that receives adhesive that drains from
section 610. Section 620 is also equipped with a heat jacket 623,
so that the adhesive that drains into reservoir 621 also remains at
elevated temperature. Section 620 is also equipped with cylinder
633 that provides pressure to reservoir 621. Pressure is provided
in the form of an inert atmosphere (i.e., inert from the
perspective of adhesive cure). Examples of inert atmospheres, in
this context, are pressurized moisture free air, argon or nitrogen
gas. If air is selected, it is advantageous if the air is
superheated (i.e. heated with little to no moisture) to ensure that
the adhesive remains at elevated temperature and does not begin to
cure when in the apparatus 600. As previously noted, the specific
temperature will depend upon the adhesive, and the selected
adhesive will have a melting temperature that will not damage the
fabric panels to be joined by the adhesive. Although some fabrics
can tolerate temperatures in excess of 400.degree. F., typically
temperatures will be 350.degree. F. or less. Because of
manufacturing considerations (lower energy costs, operator safety,
etc.) temperatures in the range of about 260.degree. F. to
280.degree. F. are considered advantageous and adhesives with
melting temperatures in this range are therefore preferred. The
pressure forces the adhesive from reservoir 621 out through nozzle
624. Nozzle 624 is connected by hose (not shown) to an adhesive
delivery device (e.g., the slot nozzle illustrated in FIG. 13). The
apparatus also has intermediate plate 630 which is illustrated in
detail in FIG. 16. The apparatus has top lid 661, which is
illustrated in detail in FIG. 17.
[0093] FIG. 16 illustrates intermediate plate 630 that separates
the top section 610 from the bottom section 620 in FIG. 15. Plate
630 is equipped with annular seals 631 to ensure that ambient air
does not enter the apparatus 600, and more particularly the
container 611 or reservoir 621, when sealed. Plate 630 is also
equipped with a cylinder 632 to ensure that an air tight seal is
maintained when the apparatus is sealed. Plate 630 is also equipped
with a retractable knife 633 for opening the adhesive container
placed in upper section 610. The retractable knife 633 is
pneumatically actuated to pierce the bottom of the can of adhesive
once placed in the apparatus 600.
[0094] Referring to FIG. 17, container 611 is shown being placed in
top section 610 of apparatus 600. Lid 661 pivots to permit the
placement of the container 611 within the apparatus. The heating
jacket 612 surrounds the container 611 when placed in the
apparatus, providing uniform heating to the adhesive within the
container 611. The top section 610 is spring loaded 623 to ensure
contact and, therefore, good heat conduction, between the jacket
612 and the container 611. Cover 660 is equipped with pneumatic can
punch mechanism 662. This mechanism 662, when actuated, will
puncture a hole in the container 611. Alternate embodiments employ
an external punch. The hole permits the adhesive to flow from the
container 611 into the underlying reservoir 621 (FIG. 15) when the
bottom of the container 611 is punctured by the retractable knife
633 (FIG. 16).
[0095] As previously noted, one example of a suitable adhesive is
supplied in cans as a thick paste, which must be heated to be
converted to the liquid form in which it is used. It takes about 20
to about 30 minutes to heat the adhesive to a temperature
sufficient to cause it to melt into a liquid form that is
sufficiently fluid to be applied onto the material. As previously
noted, the adhesive in liquid form must be kept sealed from the
ambient atmosphere to ensure that the adhesive does not begin to
cure while in the apparatus. The adhesive can be retained in the
apparatus under a blanket of dry, moisture free air or nitrogen and
maintained in an uncured state. Since the apparatus has a lower
reservoir 621, an empty container 611 can be replaced with a full
can and the adhesive in the new can heated and melted before the
lower reservoir is empty of adhesive. This ensures continuous
operation.
[0096] As previously noted, the adhesive cures in the presence of
ambient air. In order to affect a more rapid cure, cool, moist air
(e.g., room temperature and at least forty percent humidity) is
directed onto the newly formed seam. The cool, moist air causes the
cure to occur at a faster rate. This allows the seam to set more
quickly, making it less likely to come apart when the garment is
moved following seam formation.
[0097] Referring to FIG. 18, there is illustrated a holder 700 that
provides a contoured surface that mimics the contour of the
adhesive seam. Specifically holder 700 had a surface 710 that
supports a plurality of stands 720. These stands 720 have a
pedestal portion 725 that supports a contoured top portion 730. The
contoured top portion is configured to mimic the contour of the
adhesive seam 735 for bra cup 740. Curing the bra cups 740 in this
manner avoids placing the fabric panels 745 on a surface that will
cause the fabric panels to wrinkle during cure. Wrinkles in the
fabric panel during cure can cause the seam 735 to deform during
cure, which can result in a cured seam with a less than uniform,
and therefore less desirable, appearance.
[0098] Although the invention herein has been described with
reference to particular embodiments, it is to be understood that
these embodiments are merely illustrative of the principles and
applications of the present invention. It is therefore to be
understood that numerous modifications, additions and substitutions
may be made to the illustrative embodiments without departing from
the scope and spirit of the invention, or that other arrangements
may be devised without departing from the spirit and scope of the
present invention.
* * * * *