Note: Descriptions are shown in the official language in which they were submitted.
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SELF-INFLATABLE AIR CUSHION
BAC GROUND OF THE INVENTION
The present invention relates to a self inflatable air
cushion for use in shoes. and more particularly to such a self
inflatable air cushion which comprises a collapsible pienum
chamber, a support chamber, and an one-way valve connected
between the plenum chamber and the support chamber for
permitting air be driven from the collapsible pienum into the
support caamber by compressing t:~e plenum chamber with the
foot.
4 resular air cushion for shoes is generally comprised of a
collapsible three-dimensional body defining a plurality of air cells
and a plurality of passages connected between the air cells, and an
air valve connected to the passages and disposed outside the sole
IS of the shoe. When the air cushion is interlude, an air pump is
attached to the air valve and operated to pump air into the air cells.
If the inside pressure of the air cushion is excessively high, it
cannot be regulated.
SITMMARY OF TH . INVENTION
According to one aspect of the present invention, the
self-inflatable air cushion comprises a support chamber, a
collagsiblc plenum chamber surrounded by the support chamber
and having an air hole, an air passase communicating between the
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support chamber and the collapsible plenum chamber. an one-way
valve mounted in the air passage which permits air to pass from the
plcnum chamber to the support chamber. When the pienum
chamber is compressed with the foot, air is forced out of the
pienum chamber through the one-way valve into the support
chamber. When the plenum chamber is released, outside air is
drawn into the plenum chamber through its air hole. According
another aspect of the present invention. a relief valve or pressure
regutatin~ chamber is provided to regulate the inside pressure of
the support chamber to the desired level. According to still
another aspect of the present inv~r.::on, a pressure accumulation
chamber is provided having one end connected to the pienum
chamber through an one-way valve, which permits air to flow from
the plenum chamber to the pressure accumulation chamber, and an
opposite end connected to the support chamber through an one-way
valve. which permits air to flow from the pressure accumulation
chamber to the support chamber. When the plenum chamber is
compressed, air pressure is driven from the plenum chamber into
the pressure accumulation chamber. However, because the
support chamber simultaneously receives an external pressure, the
air pressure of the pressure accumulation chamber is stopped from
passing to the support chamber. When the external pressure is
released from the support chamber, the air pressure of the pressure
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accumulation chamber is allowed to pass to the inside of the
support chamber.
~ BRIEF DESC'RIPT10N OF THE DRAWINGS
Fig. 1 is an elevational view of a self-inflatable air cushion
according to one embodiment of the present invention;
Fig. 2 is an elevational view of a self-inflatable air cushion
according to an alternate form of the present invention;
Fig. ? is an applied W ew of the present invention, showing
the self inflatable air cushion mounted in an msoie of a shoe and
IO operated:
Fig. 4 is a plain view shomng another alternate four: c;f the
present invention;
Fig. 4A is a sectional view taken along line 10A-IOA of
Figure 4;
Fig. 4B shows the turning direction of the plenum chamber
of the embodiment shown in Figure 4;
Fig. 4C shows the pienum chamber of the embodiment of
Figure 4 arranged in the top recess of the corresponding support
chamber;
Fig. 4D is a sectional view taken along Iine IOD-IOD of
Figure 4:
Fig. 5 is a sectional view of still another alternate form of
the present invention. showing the installation of the pressure
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regulating rod in the pressure regula:ing chamber; and
Fia. S A is a sectional view taken along line 11 A-11 A.
ZlFTil1 Fn nFS~Rmrlclnr c~FTHE PREFER
Referring to Figure 1, a self-inflatable air cushion la is
shown comprising a support chamber 1, an open space 21
surrounded by the air chamber 1, a pienum chamber 10 disposed in
the open space 21 and having an air hole 31, an air cylinder 22
having its one end, namely, the rear end disposed in
commumcaaon with the support chamber i. a connecting tube 33
connected bem~een the pienum chamber i0 and the air cylinder Z2,
an one-way valve i01 mounted in the air cylinder 22 which permits
air to pass from the plenum chamber 10 through the air cylinder 22
to the inside of the support chamber i, and a relief valve 103
mounted in one end, namely, the front end of the air cylinder 22.
1$ Fisure 2 shows an alternate form of the present invention.
According to this alternate form. the air cushion 1 comprises a
support chamber 1, an air cylinder 22 connected to the support
chamber 1 at one side, a pienum chamber 10 spaced from the air
cylinder 22 at one side opposite to the support chamber 1, and a
connecting tube 34 connected between one end, namely, the rear
end of the air cylinder 22 and the polonium chamber 10, an one-
way valve 101 mounted in the air cylinder 22 for permitting air to
be delivered from the plenum chamber 10 to the support chamber 1.
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and a relief valve 103 mounted in one end. namely, the front end of
the air cviinder 22.
Referring to Figure 3, the air cushion lA is mounted inside
an insole 6 of a shoe with the plenum chamber 10 projecting out of
a top hole 6I of the insole 6 at the heel area. When the user's foot
is stepped on the pienum chamber I0, the plenum chamber 10 is
collapsed, and the inside pressure of the plenum chamber 10 is
forced through the connecting tube 33 and the air cylinder 22 into
the support chamber 1. When the user's foot is lifted from the
collapsed plenum chamber 10, outside air is immediately drawn
into the plenum chamber 10 due to an air pressure difference
between the inside pressure of the pienum chamber 10 and the
atmospheric pressure. When the user continuously steps on the
plenum chamber 1 of the air cushion lA, the support chamber I
IS will be inflated to ~ the saturated status. When the support
chamber 1 is fully inflated. the support chamber 1 supports the
plenum chamber 10 against outside pressure. Further, through
the relief valve I03, the user can adjust the pressure of the support
chamber 1 to the desired level.
Referring to Figure 4, outside air passes from the air hole
31 into the plenum chamber I0. When the user's foot gives a
pressure to the plenum chamber I0, the air hole 31 is stopped by
the user's foot and the inside air of the plenum chamber 10 is
s
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forced by the pressure of the user's foot to flow through an air
passage 3b to a pressure regulating chamber 301 and then through
the aforesaid one-way valve 101 to a pressure accumulation
chamber 6. The pressure accumulation chamber G is arranged at a
place in which the pressure accumulation chamber 6 bears no
pressure when the support chamber 1 or the plenum chamber 10
receives a pressure from the user's foot. therefore. compressed air
is allowed to be forced out of the pienum chamber 10 into the
pressure accumulation chamber 6 and then through an one-way
valve 102 into the support chamber 1 via an air passage 3a.
Referring to Figures 4B, 4C and 4D, the eienum chamber
10 can be turned backwards through about 180° and arranged in a
top recess l0a of the support chamber 1 with its air hole 31 facing
upwards.
Referring to Figures 5 and SA, a pressure regulating rod
301 is mounted in a pressure regulating chamber 301. The
pressure regulating rod 301 is a hollow rod having a longitudinal
center hole 52, a plurality of recessed holes 54, and a plurality of
radial through holes 52 in communication with the longitudinal
center hole 52. The recessed holes 54 and the throush holes 52
are arranged corresponding to distribution charctbers 51, the one-
way valve 101. and an air passage 3a. By turning the pressure
regulating rod 30I. the pressure of the pressure accumulation
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chamber 6 and the support chamber 1 is regulated. When the
through holes 52 are moved way from the air passage 3a,
compressed air is prohibited to pass from the penned chamber IO to
the support chamber 1. When the air passage 3a, the through
holes 52 and the distribution chambers 51 are set into
communication with one another through the longitudinal center
hole 53, air pressure is allowed to pass into the pressure
accumulation chamber 6 subject to the volume of the distribution
cizambers 51. Assume the inside volume of the penned chamber
i0 10 = A, the inside volume of the distribution chambers 5! = B, the
inside volume of the plenum chamber 10 when collapsed = C, thus
P1 V 1'P2V2=n. the pressure of the pienum chamber 10 after
compressed is Pb=PaA/H+C, therefore when the greater the inside
volume B of the distribution chambers 51, the smaller the air
pressure Pb of the pressure accumulation chamber 6 will be.
When the through holes 52 and the pienum chamber 10 arc
disposed in communication with an air passage 3c, air is allowed to
be squeezed out of the plenum chamber 10 through the air passage
3c to other air circulation area. Therefore, the air cushion lA can
also improve the ventilation of the shoe.
It is to be understood that the drawings are designed for
purposes of illustration only, and are not intended as a definition
of the limits and scope of the invention disclosed.
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