Note: Descriptions are shown in the official language in which they were submitted.
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METHOD FOR FABRICATING A FOOTWEAR SOLE /
TECHNICAL FIELD
[001] The present invention relates to a technology for making footwear, and
particularly relates to a mould for making shoe soles and its usage.
BACKGROUND OF THE INVENTION
[002] Ordinary shoe soles are generally formed up by one or two types of
materials,
which have poor air permeability and tend to fatigue the feet after long-term
wear.
Besides, they fit badly with the feet and may easily cause the fore part of
the foot to
deform if worn for a long time.
[003] WO 2010/012401 by O'Connor et al. discloses a footwear outsole 1 made of
a
lather lamina 3 with ground contact lugs 4 moulded at the bottom of the layer
lamina 3
and a series of very thin parallel strips 9 bonded with adhesive at the top of
the leather
lamina 3. An outsole moulding 2 may be stitched 6 or moulded around the outer
edges
of the leather lamina 3. A problem with such outsolel is that the lugs 4 and
strips 9 may
become detached from the leather lamina, during use for example, because the
bonding between the lamina 3 and the lugs 4 and strips 9 is not strong enough.
Also,
using stitching 6 to bond the outsole 2 adds an additional stitching step
using stitching
machinery in addition to the other manufacturing and moulding steps using
moulding
machinery and potentially increases the costs and complexity.
[004] There is therefore a need in the market for a more durable shoe sole,
while
maintaining fabrication costs and complexity at low levels.
[005] The present invention discloses a technology which overcomes the
above-mentioned shortcomings by providing a sole which can fit snugly with the
foot,
has good air permeability and elegant appearance. It can automatically adapt
to the
shape of the foot, and is therefore suitable for long-term wear.
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SUMMARY OF INVENTION
[006] According to a preferred embodiment of the present invention, there is
provided
a method for forming a footwear sole comprising a fore sole and a rear sole.
The
method comprises: providing a midsole layer having one or more midsole
injection
holes and one or more midsole bores distributed thereon, the midsole injection
holes
and the midsole bores extending between an underside of the midsole layer and
an
upper surface of the midsole layer; providing a first female mould comprising
one or
more first downward concave cavities and first raised areas; placing said
midsole layer
onto said first female mould, and aligning said midsole injection holes and
said midsole
bores with said first downward concave cavities provided in said first female
mould;
providing a first male mould comprising a first injection area comprising one
or more of
first bores and one or more first injection holes; assembling and fixing said
first male
mould and said first female mould so that each of said midsole bores and said
midsole
injection holes are respectively aligned with each of said first bores and
each of said first
injection holes; infusing a first formula plastic into said first male mould
by way of said
first injection holes and said midsole injection holes into said first
downward concave
cavities, wherein said first formula plastic is channeled through each of said
first
injection holes and each of said midsole injection holes into each of said
downward
concave cavities and shaped up resulting in raised soles lines on said fore
sole, and
further wherein said first formula plastic inside each of said first downward
concaves
passes through each of said midsole bores and into each of said first bores to
form one
or more protuberances which are embedded with said midsole layer; splitting
said first
male mould and said first female mould to remove said midsole layer comprising
said
raised sole lines and said protuberances; taking said midsole layer out of
said first male
mould and said first female mould and placing said midsole layer into a
footwear
sole-shaped second mould for injection moulding with a second formula plastic
to form
one or more second raised sole lines on the upper surface of the midsole
layer, the
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second raised sole lines being embedded with the protuberances to thereby
anchor the
first raised sole lines with the second raised sole lines.
[007] Advantageously, the provision of bores in the midsole layer allow for
better
anchoring of the first sole lines on one side of the midsole layer with the
second sole
lines on the other side of the midsole layer by means of the protruding
protuberances
being embedded with the second formula plastic.
[008] Preferably, the sole mould is used to fabricate high-quality soles with
great
efficiency, wherein the sole features good air permeability and is suitable
for long-term
wear because it can fit snugly with the foot by adapting itself automatically
to the shape
of the foot.
[009] Preferably, the second mould may further include a second female mould
and a
second male mould, both configured in the same shape as a complete foot sole
and can
fit into each other. Further, the aforementioned first female mould and the
first male
mould, both resembling the fore part of the sole, also match the fore part of
the
sole-shaped second female mould and the second male mould. The said second
female mould further includes a second downward concave in the same shape as
and
at the corresponding position of the first downward concave of the first
female mould.
The said second male mould further features a second injection area in the
same shape
as and at the corresponding position of the second downward concave. Still
further, a
second injection hole (which passes through the leather layer) is designed on
the said
second injection area. The second male mould further features an upward-
concaved
third injection area in the rear part of the sole, as well as a second
injection hole (which
passes through the leather layer) in the said third injection area. The
leather layer,
having been processed by the first female mould and the first male mould, is
further
processed by the second female mould and the second male mould, generating an
injection-moulded shoe sole with an embedded leather layer. Meanwhile, a
raised
injection area is formed on the upper side of the said leather layer.
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[010] A middle plate may be inserted between the second female mould and the
second male mould when the two are assembled to process the leather layer
through
injection moulding, so as to produce a cambered or arcuate shoe sole.
[011] Preferably, the first injection hole passes through the first male mould
through an
injection channel; the second injection hole passes through the second male
mould
through an injection channel.
[012] The soft plastic used may be thermoplastic polyurethane (TPU).
Preferably, the
first formula plastic is softer than said second formula plastic.
[013] Preferably, the cylindrical bores and the injection holes have a
diameter of about
to 2mm tol0mm.
[014] The sole mould described in this Invention is simple in structure and
easy to
operate. It is capable of manufacturing quality foot soles of good air
permeability with
high efficiency. Moreover, these shoe soles can perfectly match the feet by
automatically adapting themselves to the shape of the feet, and are therefore
suitable
for wear for a long time. Moreover, the product yield is relatively high.
BRIEF DESCRIPTION OF THE DRAWINGS
[015] Fig. 1 is a side sectional view of a shoe sole formed by the sole mould
and
method, according to a preferred embodiment of the present invention;
[016] Fig. 2 is a top view of the shoe sole of Fig. 1;
[017] Fig. 3 is a sectional view of a first female mould and a first male
mould in an
assembled position, according to a preferred embodiment of the present
invention;
[018] Fig. 4 is a sectional view of a second female mould and a second male
mould in
an assembled position, according to a preferred embodiment of the present
invention;
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[019] Fig. 5 is a top view of two leather layers used by a sole mould for
making shoe
soles, according to a preferred embodiment of the present invention;
[020] Fig. 6 is a top view of a left and right first female moulds, according
to a preferred
embodiment of the present invention;
5 [021] Fig. 7 is a bottom view of a left and right first male moulds,
according to a
preferred embodiment of the present invention;
[022] Fig. 8 is a sectional view of the leather layer of Fig. 5 after being
injection
moulded using a first female mould and a first male mould, according to a
preferred
embodiment of the present invention;
io [023] Fig. 9 is a top view of a left and right second female moulds,
according to a
preferred embodiment of the present invention;
[024] Fig. 10 is a bottom view of a left and right second male moulds,
according to a
preferred embodiment of the present invention;
[025] Fig. 11 is a flow process of one example of a method for using the sole
mould,
according to a preferred embodiment of the present invention; and
[026] Fig. 12 is a flow process of another example of a method for using the
sole
mould, according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[027] The preferred embodiments of this Invention will now be described by
referring
to the attached drawings.
[028] Now referring to Fig. 1 and Fig. 2, there illustrated a shoe sole 10
fabricated
according to a method of the present invention. The shoe sole has good air
permeability
and is suitable for long-time wear, as mentioned in the Background. This shoe
sole 10
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fits snugly with the foot (not shown) by automatically adapting itself to the
shape of the
foot. The main body or midsole layer 12 of the fore sole 14 is illustratively
a leather layer
which is primarily made of leather materials. By way of injection-moulding
soft plastics,
one or more first raised sole lines 16 and one or more second raised sole
lines 18 are
formed respectively on an underside 20 of the midsole leather layer 12 to thus
form an
outer sole portion 19 and an upper surface 22 of the midsole leather layer 12
to thus
form an inner sole portion 17. A rear part 24 of the sole 10 is also obtained
by
injection-moulding the same plastics and is integrated with the leather layer
12 to
constitute a complete shoe sole 10. The raised sole lines 16, 18 are shaped
like ribs that
1o define channels in between these ribs, which ensure good air circulation.
[029] Now referring to Fig. 3, Fig. 4 and Fig. 5, in addition to Fig. 1, there
is illustrated a
sole mould according to an illustrative embodiment of the present invention.
The sole
mould includes two parts: a first mould 26 which resembles a fore sole 14 and
a second
mould 28 which has the shape of a complete foot sole. The first mould 26 and
the
second mould 28 are used successively to produce the shoe sole 10. Firstly,
the first
mould 26 is used to treat the leather layer 12, in particular the fore part 14
of the shoe
sole 10, by injection moulding, which forms the one or more first raised sole
lines 16 on
the underside 20 of the leather layer 12. Secondly, the second mould 28 is
used to treat
the leather layer 12 bearing the first raised sole lines 16, resulting in one
or more
second raised sole lines 18 on the upper surface 22 of the leather layer 12.
Meanwhile,
the rear part 24 of the shoe sole 10 is obtained by injection-moulding soft
plastics in the
second mould 28 such that the rear part 24 is integrated with the leather
layer 12. A
finished sole 10 comprising one or more second raised sole lines 18 of the
fore sole 14
on the upper surface 22 of the midsole 12 to form the inner sole portion 17
and the one
or more first raised sole lines 16 of the fore sole 14 on the underside 20 of
the shoe sole
10 to form the outer sole portion 19 is produced by the moulds, 26 and 28.
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[030] Now referring to Fig. 6, in addition to Fig.1, Fig. 3, Fig. 4 and Fig.
5, the first
mould 26 further includes a first female mould 32 and a first male mould 34,
both of
which are available as a pair to produce a pair of shoe soles 10. The first
female mould
32 and the first male mould 34 are configured in the same shape as the fore
sole 14 of
the foot and fit into each other when assembled as illustrated. The first
female mould 32
further contains one or more first downward concave cavities as in 36 and a
first raised
area 38 which when injected moulded, or infused with plastic, form the raised
sole lines
16 on the underside 20 of the leather layer 12.
[031] Now referring to Fig. 7 and Fig. 8, in addition to Fig. 3, the first
male mould 34
includes one or more cylindrical bores 40 and one or more first injection
holes 42 in a
first injection area 44 each one of which are in fluid communication with one
of the one
ore more first downward concave cavities 36 via each of one or more second
injection
hole 45 and each of one or more second cylindrical bore 47 respectively
provided for in
the layer 12. The one or more second cylindrical bores 47 and the one or more
second
injection hole 45 provide fluid communication for the plastic between the one
or more
first downward concave cavities 36 and the one or more first cylindrical bores
40 and
the one or more first injection holes 42 through the layer 12 when
respectively aligned
therewith. Illustratively, through the one or more first injection hole 42,
each of which are
in fluid communication with an injection channel 46, soft plastic is supplied
from the
injection channels 46 to be infused into the one ore more first downward
concave
cavities 36 via the one or more second injection holes 45. Once plastic is
infused into
the one or more first downward concave cavities as in 36, plastic is allowed
to pass
through the layer 12 via the one or more second cylindrical bores as in 47 and
into the
one or more of first cylindrical bore 40 provided for in the first male mould
34 such that
one or more plastic protuberances as in 49 are embedded within the midsole
layer 12
and extend from the upper surface. The first female mould 32 and the first
male mould
34 are then assembled to mould the plastic, leaving the one or more first
raised sole
lines 16 on the under side 20 of the leather layer 12.
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[032] Now referring to Fig. 9 and Fig. 10, the second mould 28 further
includes a
second female mould 48 and a second male mould 50, both of which are available
in
pair to produce a pair of shoe soles 10. The said second female mould 48 and
second
male mould 50 are configured in the same shape as a complete foot sole 10 and
can fit
into each other. Furthermore, the aforementioned first female mould 32 and the
first
male mould 34 also match the fore part 14 of the sole-shaped second female
mould 48
and the second male mould 50. The second female mould 48 further includes one
or
more second downward concave cavities as in 52 in the same shape as and at the
corresponding position of the one or more first downward concave cavities as
in 36. The
second male mould 50 further features a second injection area 54 comprising
one or
more second upward concave cavities as in 55 in the same shape as and at the
corresponding position of the one or more second downward concave cavities as
in 52.
Still further, one or more second injection holes 56 are provided in the
second injection
area 54 for each of the one or more second upward concave cavities as in 55.
[033] Still referring to Fig. 10, the second male mould 50 further features an
upward-concaved third injection area 58 to form the rear part 24 of the sole
10 when it is
injected moulded, as well as a second injection hole 56 for injecting plastic
into the third
injection area 58. The leather layer 12, having been processed using the first
female
mould 32 and the first male mould 34, is further processed using the second
female
mould 48 and the second male mould 50, generating an injection-moulded shoe
sole 10
with an embedded leather layer 12 by infusing soft plastic into the second
injection area
54 and the third injection area 58 through the second injection hole 56 and
the injection
channels 46. As a result, the one or more second raised sole lines 18 are
formed on the
upper surface 22 of the leather layer 12.
[034] It should be noted that the soft plastic being used for injection
purposes for the
sole mould described herein is illustratively thermoplastic polyurethane
(TPU).
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Illustratively, the plastic used to form the one ore more first raised sole
lines 16 may be
harder than the plastic used to form the one or more second raised sole lines
18.
[035] Now referring back to Fig. 1 and Fig. 4, the sole mould provided in the
present
Invention further includes a middle plate 60, which is inserted between the
second
female mould 48 and the second male mould 50 when the two are assembled for
injection moulding the leather layer 12. The ultimate purpose is to produce a
curved
shoe sole, for instance the curved rear part of high-heeled leather shoes for
women.
[036] The sole mould described in this Invention is simple in structure and
easy to
operate. It is capable of manufacturing quality foot soles of good air
permeability with
high efficiency. Moreover, these shoe soles 10 can perfectly match the feet by
automatically adapting themselves to the shape of the feet, and are therefore
suitable
for wear over a long period of time. Moreover, the product yield is relatively
high.
[037] Now referring to Fig. 12, there is provided an illustrative example of
the method
of using the sole mould which comprises the following steps.
[038] Step S102: Assemble the fore sole-shaped first mould 26 onto an
injection
machine (not shown). After that, place the leather layer 12 into the first
mould 26 for
injection moulding to form the first raised area 38 on the underside 20 of the
leather
layer 12 comprising one or more first raised sole lines 16.
[039] Step S104: Take the leather layer 12 out of the first mould 26 and put
it into the
foot sole-shaped second mould 28 for injection moulding to produce a shoe sole
10 with
an embedded leather layer 12 comprising the second raised injection area 54 on
the
upper surface 22 of the leather layer 12 comprising the one or more second
raised sole
lines 18.
[040] Now referring to Fig. 12, there is provided another illustrative example
of the
method of using the sole mould is composed of the following steps :
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[041] Step S202: Assemble the fore sole-shaped first female mould 32 of the
first
mould 26 onto the injection machine. Place the leather layer 12 on top of the
first female
mould 32 with the underside 20 facing downwards and align the each pre-
designed one
or more second cylindrical bores 47 and one or more second injection holes 45
on the
5 leather layer 12 with the each of the one or more first downward concave
cavities 36 of
the first female mould 32.
[042] Step S204: Assemble and fix the fore sole-shaped first male mould 34 and
the
first female mould 32, making sure that each of the first cylindrical bores 40
and each of
the first injection holes 42 located on the first male mould 34 are aligned
with each of
10 second cylindrical bores 47 and each of the second injection holes 45 on
the leather
layer 12 respectively. Then, place a puller plate 64 on top of the first male
mould 34.
[043] Step S206: By way of the one or more first injection hole 42 and the one
or more
injection channels 46, infuse the soft plastic into the first male mould 34 by
using an
injection machine (not shown). The soft plastic, after going through the one
or more first
injection holes 42 on the first male mould 34 is channelled into the one or
more first
downward concave cavities 36 of the first female mould 32 and shaped up,
resulting in
the first raised area 38 on the underside 20 of the leather layer 12 to form
the first one or
more first raised sole lines 16. Further, the soft plastic inside the one or
more first
downward concave cavities 36 moves through the one or more second cylindrical
bores
47 of the leather layer 12 and into the one or more first cylindrical bores 40
to form one
or more pyramidal protuberances 49, which are integrated with the leather
layer 12.
After that, the first male mould 34 and the first female mould 32 are split to
remove the
leather layer 12 bearing a first injection area 44 on the underside 20.
[044] Referring back to Figure 5, it is preferable to pre-punch the midsole
layer 12 to
form holes matching with the cylindrical bores 47 and the injection holes 45
prior to
placing the midsole 12 on top of the first female mould 32. Alternatively, the
cylindrical
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bores 47 and the injection holes 45 may be punched in the midsole 12 once the
midsole
is in the first female mould 32.
[045] Step S208: Assemble the foot sole-shaped second female mould 48 of the
second mould 28 onto the injection machine and place the middle plate 60 on
the said
second female mould 48. Lay up the leather layer 12 onto the middle plate 60,
making
sure that the underside 20 of the leather layer 10 faces downward and that the
first
injection area 44 on the underside 20 of the leather layer 10 shall match with
the second
downward concave cavities 52 of the second female mould 48. The final purpose
is to
produce arcuation on the leather layer 12;
[046] Step S210: Assemble and fix the foot sole-shaped second male mould 50
and
the second female mould 48 of the second mould 28, making sure that the second
injection area 54 of the second mould is aligned with the one or more second
downward
concave cavities 52. When aligned, the one or more pyramidal protuberances 49
on the
leather layer 12 are suspended, or project, inside the second injection area
54. Then,
place the puller plate 64 on top of the second male mould 50.
[047] Step S212: By way of the one or more second injection holes 56 on the
second
male mould 50 and the one or more injection channels 46, infuse the soft
plastic into the
second male mould 50 by using an injection machine. The soft plastic is
moulded into a
shoe sole 10 to combine with embedded leather layer 12 and the one or more
pyramidal
protuberances 49 inside the second injection area 54 and the third injection
area 58.
During this process, the one or more pyramidal protuberances 49 as mentioned
in
Steps S206 and S210 are embedded into the plastic injected into the one or
more
second upward concave cavities 52, therefore leaving a second raised injection
area 54
of second raised sole lines 18 on the upper surface 22 of the leather layer
12.
[048] Easy to operate, the sole mould described in this Invention is capable
of
manufacturing quality shoe soles of good air permeability with high
efficiency. These
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shoe soles can perfectly match the feet by automatically adapting themselves
to the
shape of the feet, and are therefore suitable for wear over a long time.
Moreover, the
product yield is relatively high.
[049] The shoe sole is particularly comfortable to wear when using a leather
midsole.
Indeed, because of the relatively high elasticity of leather, the shoe sole
may wrap up
feet of different shapes. Because parts of the leather midsole are not covered
with
plastic, it provides with good air permeability and ventilation. The shoe sole
is
comfortable, cooler and drier compared to other existing shoe soles and solves
problems of long-time wearing, poor air permeability, dampness and heating.
