Note: Descriptions are shown in the official language in which they were submitted.
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TRIM ATTACHMENT PROCESS
Field of the Invention
[0001] The invention relates to a trim cover for a motor vehicle seat. More
particularly, the invention relates to a method of attaching a trim cover to a
foam pad
of a motor vehicle seat.
Background of the Invention
[0002] A seat cushion or seat back of a motor vehicle seat is typically formed
from a
foam pad covered by a trim cover. Typically, the trim cover and the foam pad
are
attached to one another by an adhesive material or by sewing the trim cover to
the
foam pad. Various materials can be used for the trim cover, including cloth,
vinyl,
and leather. Leather is a particularly desirable trim cover material due to
its luxurious
appearance and comfortable feel. One problem that is, however, present with
the use
of leather trim covers is the formation of wrinkles or creases along the
leather as it is
stretched under a load. This detracts from the overall appearance of the seat.
Typically, the wrinkling is the result of an insufficient attachment between
the leather
trim cover end the foam pad.
[0003] Thus, there is a need for a method of attaching a trim cover,
particularly a
leather trim cover, to a foam pad that eliminates wrinkles along the leather
trim cover.
Summary of the Invention
[0004] According to one aspect of the invention, a method of attaching a
leather trim
cover to a foam pad utilizes a laminate. The laminate includes a double-sided
adhesive film secured to a top surface and a heat-activated adhesive agplied
along a
bottom surface. The method includes the steps of placing the top surface of
the
laminate against the leather trim cover and applying pressure of the pressure
sensitive
adhesive film against the leather trim cover to bond the laminate thereto;
applying the
bottom surface of the laminate to the foam pad; and heating the bottom surface
of the
laminate to bond the heat-activated adhesive to the foam pad and couple the
leather
trim cover thereto.
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Brief Description of the Drawings
[0005] Advantages of the present invention will be readily appreciated as the
same
becomes better understood by reference to the following detailed description
when
considered in connection with the accompanying drawings wherein:
[0006] Figure 1 is a perspective view of a motor vehicle seat including a
leather trim
cover;
[0007] Figure 2 is a cross-sectional view of the attachment of the leather
trim cover to
a foam pad according to a method of the invention;
[0008] Figure 3 is a cross-sectional view of a laminate utilized to attach the
leather
trim cover to the foam pad; and
[0009] Figure 4 is a cross-sectional view similar to Figure 2 including a foam
foundation pad disposed between the leather trim cover and the foam pad.
Detailed Description of the Preferred Embodiment
[0010] Referring to Figure 1, a seat 10 is provided for supporting an occupant
within
a motor vehicle passenger compartment 12. The seat 10 includes a trim cover,
generally indicated at 14, which provides the seat 10 with an aesthetically
pleasing
appearance that complements the passenger compartment 12.
[0011] Referring to Figure 2, the trim cover 14 includes an outer or support
surface
16 and an opposing inner surface 18. In a preferred embodiment, the trim cover
is a
natural leather trim cover 14, such as cowhide, horse hide, or another animal
hide.
The trim cover 14 may also be formed from a synthetic or artificial leather
material.
[0012] The leather trim cover 14 covers a contoured cellular foam pad 20,
which is
well-known to those of ordinary skill in the art, to form the seat 10. It
should be
appreciated that one or more leather trim covers 14 may be utilized to fully
cover the
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foam pad 20. The foam pad 20 is molded to a particular shape and includes an
upper
surface 22. Preferably, the foam pad 20 is formed from a urethane foam
material.
[0013] Referring to Figures 2 and 3, an intermediate laminate, generally shown
at 24,
is positioned between the leather trim cover 14 and the foam pad 20. The
laminate 24
is cut to compliment the shape of the leather trim cover 14. The laminate 24
includes
a base portion 26 extending between a top surface 28 and an opposing bottom
surface
30.
[0014] Referring to Figure 3, a double=sided adhesive film 32 is coupled to
the
laminate 24. The adhesive film 32 includes opposing first 34 and second 36
adhering
surfaces. The first adhering surface 34 is bonded to the top surface 28 of the
base
portion 26. The second adhering surface 36 is covered by a protective cover
38,
which is formed from a paper-like material. The cover 38 is removable to
expose the
second adhering surface 36 fox bonding the laminate 24 to the leather trim
cover 14.
The second adhering surface 36 is pressure-sensitive such that the laminate 24
must
be compressed against the leather trim cover 14 to effect the bond thereto.
Together,
the leather trim cover 14 and the laminate 24 may be placed in an oven for
preheating
at a low temperature, which makes the leather trim cover 14 more pliable.
[0025]. The bottom surface 30 of the base portion 26 is disposed along the
upper
surface 22 of the foam pad 20, as shown in Figure 2. The bottom surface 30 is
coated
with a heat-activated adhesive 40. Upon the introduction of heat, the heat-
activated
adhesive 40 is cured to bond the laminate 24 to the foam pad 20 and couple the
leather trim cover 14 thereto. The heat may be provided in various ways
including,
but not limited to, heat injection into the foam pad 20, hot air induction,
and heater
pad activation.
[0016] Alternatively, referring to Figure 4, an intermediate foam foundation
pad,
generally shown at 42, may be positioned between the leather trim cover 14 and
the
foam pad 20. When the intermediate foam foundation pad 42 is utilized, the
laminate
24 attaches the leather trim cover 14 to an upper end 44 of the foam
foundation pad
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42 instead of the foam pad 20 directly. The foam foundation pad 42 provides
additional padding below the leather trim cover 14 to give the seat '10 more
cushioning. The foam foundation pad 42 is cut to a desired shape to match or
compliment that of the leather trim cover 14 prior to the coupling therewith.
[0017] An adhesive film 46 is positioned between a lower end 48 of the foam
foundation pad 42 and the upper surface 22 of the foam pad 20. The film 46 is
coated
with a friction reducing agent, as is known to those skilled in the art. As a
result, the
film 46 prevents friction between the foundation foam pad 42 and the foam pad
20.
[0018] In a method of attaching the leather trim cover 14 to the foam pad 20
according to the invention, the protective cover 38 is removed from the top
surface of
the double-sided adhesive film 32. The exposed top surface of the adhesive
film 32 is
then placed against the inner surface 18 of the leather trim cover 14, as
shown in
Figure 2. The pressure sensitive side of the adhesive film 32 and the laminate
24 is
pressed against the leather trim cover 14 to bond the laminate 24 thereto.
Next, the
trim cover 14 and attached laminate 24 are preheated at low temperature in a
warming
oven to make the leather trim cover 14 more pliable. The bottom surface of the
laminate 24 is then applied to the foam pad 20 such that the heat-activated
adhesive
layer 40 contacts the upper surface of the foam pad 20. Finally, heat is
applied to the
laminate 24 to cure the heat-activated adhesive 40 and bond the laminate 24 to
the
foam pad 20. Thus, the leather trim cover 14 is attached to the foam pad 20.
Additionally, the seat 10 with the leather trim cover 14, laminate 24 and foam
pad 20
may also be placed in an oven in order to heat the top surface and relax the
leather
trim cover 14, aiding in removing wrinkles on the top surface thereof.
[0019] If the foam foundation pad 42 is utilized as shown in Figure 4, the
bottom
surface of the laminate 24 having the layer of heat-activated adhesive 40 is
first
applied to the upper end 44 of the foam foundation pad 42. Heat is applied to
the
bottom surface of the laminate 24. The heat cures the heat-activated adhesive
40
along the bottom surface 30 to bond the laminate 24 to the foam foundation pad
42.
The cover 38 is then removed from the top surface of the laminate 24 to expose
the
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second adhering surface 36 of the adhesive film 32 underneath. The laminate 24
is
then placed against the leather trim cover 14 such that the second pressure
sensitive
adhering surface 36 abuts the inner surface 18 of the leather trim cover 14.
The
laminate 24 is pressed against the leather trim cover 14 to bond the laminate
24
thereto. Thus, the leather trim cover 14 is attached to the foam foundation
pad 42.
The leather trim cover 14, along with the foam foundation pad 42 secured
thereto by
an adhesive bond, is secured to the foam pad 20 to form the seat 10.
[0020] The use of the laminate 24 to attach the leather trim cover 14 to the
foam pad
20 (or to the foam foundation pad 42) eliminates wrinkling along the leather
support
surface 16. The resistance to wrinkling is brought about by the continuous
bonding of
the laminate 24 to both the leather trim cover 14 and the foam pad 20. The
laminate
24 also provides additional support to the leather trim cover 14 and aids in
restricting
stretching thereof. Thus, the leather trim cover 14 is not able to float or
move relative
to the foam pad 20, thereby eliminating wrinkling along the leather trim cover
14.
[0021] It should be appreciated that the trim cover attachment method as
disclosed
may be used to form various components including, but not limited to, a seat
cushion,
seat back, bolster, headrest, door panel, instrument panel, armrest, or visor.
[0022] The invention has been described in an illustrative manner. It is to be
understood that the terminology, which has been used, is intended to be in the
nature
of words of description rather than of limitation.
[0023] Many modifications and variations of the invention are possible in
light of the
above teachings. Therefore, within the scope of the appended claims, the
invention
may be practiced other than as specifically described.
