U.S. patent application number 11/131721 was filed with the patent office on 2006-11-23 for non-spill container with flow control structure including baffle and elastic membrane having normally-closed pinholes.
This patent application is currently assigned to Insta-mix, Inc., Subsidiary A (DBA UMIX, Inc.), Insta-mix, Inc., Subsidiary A (DBA UMIX, Inc.). Invention is credited to James W. JR. Holley.
Application Number | 20060261064 11/131721 |
Document ID | / |
Family ID | 37432132 |
Filed Date | 2006-11-23 |
United States Patent
Application |
20060261064 |
Kind Code |
A1 |
Holley; James W. JR. |
November 23, 2006 |
Non-spill container with flow control structure including baffle
and elastic membrane having normally-closed pinholes
Abstract
A flow control structure for a non-spill beverage container that
includes a tube-like spout defining a flow channel, and a
substantially flat membrane supported by the spout over one end of
the flow channel, and an annular baffle mounted in the flow
channel. The membrane punctured to form multiple, substantially
round pinholes arranged in a two-dimensional pattern that remain
closed to prevent fluid and air flow under normal atmospheric
conditions, and open and to facilitate fluid flow rate through the
membrane under an applied pressure differential (e.g., when sucked
on by a child). The annular baffle defines an opening that limits
differential pressures applied to the membrane when not in use,
thereby acting in combination with the membrane to prevent leaks.
The baffle opening is also sized such that, during normal use
(e.g., sucked on by a child), substantial flow is generated through
the membrane.
Inventors: |
Holley; James W. JR.;
(Colorado Springs, CO) |
Correspondence
Address: |
BEVER HOFFMAN & HARMS, LLP;TRI-VALLEY OFFICE
1432 CONCANNON BLVD., BLDG. G
LIVERMORE
CA
94550
US
|
Assignee: |
Insta-mix, Inc., Subsidiary A (DBA
UMIX, Inc.)
Colorado Springs
CO
|
Family ID: |
37432132 |
Appl. No.: |
11/131721 |
Filed: |
May 17, 2005 |
Current U.S.
Class: |
220/203.06 ;
220/367.1; 220/714; 220/717 |
Current CPC
Class: |
A47G 19/2272
20130101 |
Class at
Publication: |
220/203.06 ;
220/714; 220/717; 220/367.1 |
International
Class: |
B65D 51/16 20060101
B65D051/16; A47G 19/22 20060101 A47G019/22 |
Claims
1. A flow control structure comprising: a tube-like spout having a
first end and a second end, the spout defining a fluid flow channel
extending from the first end to the second end of the spout, the
flow channel having a first width; a membrane connected to the
spout across the flow channel and positioned adjacent to the first
end; and a baffle located in the flow channel and spaced from the
membrane such that a first flow channel region is defined between a
first side of the baffle and the membrane, and a second flow
channel region is located on a second side of the baffle, wherein
the membrane defines a plurality of normally-closed pinholes, and
wherein the baffle defines an opening communicating between the
first and second flow channel regions, said opening having a second
width that is smaller than the first width of the flow channel.
2. The flow control structure according to claim 1, wherein the
normally-closed pinholes are formed such that when the membrane is
subjected to a relatively low pressure differential and the
membrane remains undeformed, the plurality of pinholes remain
closed to prevent fluid flow between the fluid flow channel and the
external region through the membrane, and when the membrane is
deformed in response to an applied relatively high pressure
differential, the plurality of pinholes open to facilitate fluid
flow through the membrane.
3. The flow control structure according to claim 1, wherein the
spout defines a central axis, wherein the membrane is substantially
flat and arranged perpendicular to the central axis, and wherein
the baffle parallel to the membrane, and the opening is aligned
with the central axis.
4. The flow control structure according to claim 1, wherein the
spout and the baffle respectively have a greater rigidity than the
membrane such that, when an applied pressure differential is
generated between the fluid flow channel and the external region,
the membrane undergoes a greater deformation than the spout and the
baffle.
5. The flow control structure according to claim 4, wherein the
membrane and at least an outer spout portion are integrally
connected and comprise at least one of silicone, a thermoplastic
elastomer, and soft rubber.
6. The flow control structure according to claim 4, wherein the
baffle is integrally connected to an inside surface of the
spout.
7. The flow control structure according to claim 1, further
comprising: a first member including an tube-like outer spout
portion and said membrane integrally connected to an end of the
outer spout portion; and a second member including an tube-like
inner spout portion defining said flow channel, wherein said baffle
is integrally connected to an inside surface of the inner spout
portion, wherein the outer spout portion is mounted over the inner
spout portion such that the membrane is positioned adjacent to a
first end of the inner spout portion.
8. A non-spill beverage container comprising: a container body
defining a beverage storage chamber and an opening; and a flow
control structure mounted over the opening, the flow control
structure including: a tube-like spout having a first end and a
second end, the spout defining a fluid flow channel extending from
the first end to the second end of the spout, the flow channel
having a first width; a membrane connected to the first end of the
spout such that the membrane extends across the flow channel; and a
baffle located in the flow channel and spaced from the membrane
such that a first flow channel region is defined between a first
side of the baffle and the membrane, and a second flow channel
region is located on a second side of the baffle and communicates
with the beverage storage chamber through the opening in the
container body, wherein the membrane defines a plurality of
normally-closed pinholes, and wherein the baffle defines an opening
communicating between the first and second flow channel regions,
said opening having a second width that is smaller than the first
width of the flow channel.
9. The non-spill beverage container according to claim 8, wherein
the normally-closed pinholes are formed such that when the membrane
is subjected to a relatively low pressure differential and the
membrane remains undeformed, the plurality of pinholes remain
closed to prevent fluid flow between the fluid flow channel and the
external region through the membrane, and when the membrane is
deformed in response to an applied relatively high pressure
differential, the plurality of pinholes open to facilitate fluid
flow through the membrane.
10. The non-spill beverage container according to claim 8, wherein
the spout defines a central axis, wherein the membrane is
substantially flat and arranged perpendicular to the central axis,
and wherein the baffle parallel to the membrane, and the opening is
aligned with the central axis.
11. The non-spill beverage container according to claim 8, wherein
the spout and the baffle respectively have a greater rigidity than
the membrane such that, when an applied pressure differential is
generated between the fluid flow channel and the external region,
the membrane undergoes a greater deformation than the spout and the
baffle.
12. The non-spill beverage container according to claim 11, wherein
the membrane and at least an outer spout portion are integrally
connected and comprise at least one of silicone, a thermoplastic
elastomer, and soft rubber.
13. The non-spill beverage container according to claim 11, wherein
the baffle is integrally connected to an inside surface of the
spout.
14. The non-spill beverage container according to claim 8, further
comprising: a first member including an tube-like outer spout
portion and said membrane integrally connected to an end of the
outer spout portion; and a second member including an tube-like
inner spout portion defining said flow channel, wherein said baffle
is integrally connected to an inside surface of the inner spout
portion, wherein the outer spout portion is mounted over the inner
spout portion such that the membrane is positioned adjacent to a
first end of the inner spout portion.
15. The non-spill beverage container according to claim 14, further
comprising a cap mounted over the opening defined by the container
body, the cap including an upper wall, wherein the flow control
member is mounted on the cap such that the spout extends from the
upper wall.
16. The non-spill beverage container according to claim 15, wherein
the cap includes a mounting structure integrally connected to a
bottom surface of the upper wall, and the upper wall defines an
outlet passage, and wherein the second member further comprises a
first base arranged such that the inner spout portion extends from
the first base and the flow channel extends through an opening
defined in the first base, and wherein the second member is
connected to the cap such that the first base is removably attached
to the mounting structure and the spout extends through the outlet
passage.
17. The non-spill beverage container according to claim 15, wherein
the first member further comprises a second base arranged such that
the outer spout portion extends from the second base, and wherein
the second member is attached to the mounting structure such that
the second base is pressed between the first base and the upper
wall of the cap.
18. The non-spill beverage container according to claim 15, wherein
the mounting structure comprises a cylindrical wall and includes
threads formed on an inside surface of the cylindrical wall, and
wherein the first base of the second member is a disk-shaped
structure that includes threads formed on a peripheral edge of the
disk-shaped structure that are operably engaged with the threads of
the mounting structure.
19. The non-spill beverage container according to claim 15, wherein
the mounting structure comprises a cylindrical wall and includes a
lip structure formed on an inside surface of the cylindrical wall,
and wherein the first base of the second member is a disk-shaped
structure shaped such that a peripheral edge of the disk-shaped
structure is snap-coupled the lip of the mounting structure.
20. A non-spill beverage container comprising: a container body
defining a beverage storage chamber and an opening; and a flow
control structure mounted over the opening, the flow control
structure including: a tube-like spout having a first end and a
second end, the spout defining a fluid flow channel extending from
the first end to the second end of the spout, the flow channel
having a first width; a valve structure connected to the first end
of the spout such that the valve structure is located in the flow
channel; and means located in the flow channel between the beverage
storage chamber and the valve structure for limiting dynamic fluid
pressure applied to the valve structure, said means including at
least one opening having a second width that is smaller than the
first width of the flow channel.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to fluid flow control devices
for non-spill beverage containers, and more specifically it relates
to "no drip" flow control structures for, e.g., child sippy cups
and adult "travel" mugs.
RELATED ART
[0002] Sippy cups and travel mugs represent two types of non-spill
beverage containers that utilize flow control devices to control
the ingestion of beverage in response to an applied sucking force.
Sippy cups are a type of spill-resistant container typically made
for children that include a cup body and a screw-on or snap-on lid
having a drinking spout molded thereon. An inexpensive flow control
element, such as a soft rubber or silicone outlet valve, is often
provided on the sippy cup lid to control the flow of liquid through
the drinking spout and to prevent leakage when the sippy cup is
tipped over when not in use. Adult non-spill "travel" mugs are
usually fabricated from a thermally insulating material, and have a
narrow spout that restricts flow of a hot beverage (e.g., coffee).
A valve similar to that used on child sippy cups is sometimes
incorporated into such travel mugs to prevent spills.
[0003] "No drip" sippy cup flow control valves typically include a
sheet of the elastomeric material located between the inner cup
chamber and the open end of the drinking spout that defines one or
more slits formed in an X or Y pattern. As a child tilts the
container and sucks liquid through the drinking spout, the slits
yield and the flaps thereof bend outward, thereby permitting the
passage of liquid to the child. When the child stops sucking, the
resilience of the causes the slits to close once more so that were
the cup to be tipped over or to fall on the floor, liquid cannot
pass out of the container through the drinking spout.
[0004] One problem associated with conventional non-spill cups is
that the elastomeric material used to form the slit-type "no drip"
flow control valves can fatigue in the region of the slits and/or
become obstructed over time, and the resulting loss of resilience
can cause leakage when the slit flaps fail to fully close after
use. This failure of the slit flaps to close can be caused by any
of several mechanisms, or a combination thereof. First, repeated
shearing forces exerted at the end of each slit due to repeated use
can cause tearing of the elastomeric material in this region,
thereby reducing the resilient forces needed to close the slit
flaps after use. Second, thermal cycling or mechanical cleaning
(brushing) of the elastomeric material due, for example, to
repeated washing, can cause the elastomeric material to become less
elastic (i.e., more brittle), which can also reduce the resilience
of the slit flaps. Third, solid deposits left by liquids passing
through the slits can accumulate over time to impede the slit flaps
from closing fully.
[0005] A second problem associated with conventional non-spill cups
is that the "no drip" flow control valves are typically located
inside the short, straw-like drinking spout such that a small, open
upper section of the spout is located above the valve. During each
sip, liquid is drawn through the valve (which is pulled open by the
applied suction), and the passes through the open upper section of
the drinking spout into the drinker's mouth. Because the valve
closes at the end of each sip (i.e., when the applied suction is
terminated), a small amount of liquid is typically "trapped"
(retained) in the upper section (i.e., between the now-closed valve
and the open end of the drinking spout). Because the upper end of
the drinking spout is open to the air, this small amount of liquid
can drip or be shaken from the end of the drinking spout and
create, for example spots on a light colored carpet.
[0006] What is needed is a flow control structure for non-spill
sippy cups and travel mugs that exhibits superior non-spill,
no-drip characteristics. What is also needed is a flow control
structure that automatically adjusts its fluid flow rate to the
applied suction, and avoids the clogging and tearing problems
associated with conventional slit-type elastic flow control
structures. What is also needed is a non-spill beverage container
that omits the small, open upper section of the drinking spout.
SUMMARY
[0007] The present invention is directed to a flow control
structure for a non-spill beverage container (e.g., a child sippy
cup or an adult travel mug) that includes a tube-like spout
defining a relatively wide flow channel, a membrane extending
across an end of the flow channel, and a baffle supported in the
flow channel that provides a small opening between a beverage
storage chamber and the membrane. The membrane is formed from a
suitable elastomeric material (e.g., soft rubber, thermoplastic
elastomer, or silicone) that is punctured to form multiple,
substantially round pinholes that remain closed to prevent fluid
flow through the membrane and flow channel under normal atmospheric
conditions (i.e., while the membrane remains non-deformed), thereby
providing a desired "no drip" characteristic. The baffle further
enhances this "no drip" characteristic by acting to limit fluid
pressure in the region between the baffle and the membrane (i.e.,
in the presence of a higher fluid pressure downstream of the
baffle). Conversely, when subjected to such an applied pressure
differential (e.g., when sucked on by a child), the membrane
stretches (deforms), thereby causing some or all of the pinholes to
open and to facilitate fluid flow rate through the membrane, which
is substantially unimpeded by the baffle under these conditions.
Because the amount that the pinholes open, and the associated fluid
flow through the pinholes, is related to the applied pressure
differential, the present invention provides a flow control
structure that automatically adjusts its fluid flow rate to the
applied suction. In addition, because the pinholes are
substantially round, the pinholes resist the clogging and tearing
problems associated with slit-type flow control structures.
[0008] According to another embodiment of the present invention, a
non-spill beverage container includes a container body, a cap
mounted over an open end of the container body, and a flow control
structure mounted on the cap such that a spout of the flow control
structure extends through an opening in the cap. The flow control
structure includes an outer, relatively flexible member that
includes a tube-like outer spout portion and the membrane, and an
inner, relatively rigid member that includes the baffle. The inner
member includes a base that is screwed, snap-coupled or otherwise
secured to the cap, and an inner spout portion that forms the flow
channel. The outer member mounts over the inner spout portion such
that the membrane is positioned at the upper end of the spout.
Because the membrane is located at the end of the spout, when a
user finishes drinking and the pinholes close, beverage that may be
retained in the flow channel is prevented from dripping from the
spout by the membrane, thus avoiding the dripping problem
associated with conventional non-spill beverage containers.
[0009] The present invention will be more fully understood in view
of the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a perspective side view showing a flow control
structure according to a generalized embodiment of the present
invention;
[0011] FIGS. 2(A) and 2(B) are top and cross-sectional side views,
respectively, showing the flow control structure of FIG. 1;
[0012] FIGS. 3(A) and 3(B) are simplified diagrams illustrating
tensile forces generated in flat and curved membranes;
[0013] FIGS. 4(A) and 4(B) are simplified enlarged cross-sectional
views showing the opening of a pinhole formed in the flow control
element of FIG. 2 during operation;
[0014] FIGS. 5(A) and 5(B) are cross-sectional side views showing
the flow control structure of FIG. 1 during operation.
[0015] FIG. 6 a cross-sectional side view showing a non-spill
beverage container including a flow control structure according to
an exemplary embodiment of the present invention;
[0016] FIGS. 7(A) and 7(B) are cross-sectional side and plan views
showing an inner portion of the flow control structure utilized in
the non-spill beverage container of FIG. 6;
[0017] FIGS. 8(A) and 8(B) are cross-sectional side views showing a
process of assembling the flow control structure of FIG. 6 in
accordance with another aspect of the present invention;
[0018] FIG. 9 is a top plan view showing a cap of the non-spill
beverage container of FIG. 6;
[0019] FIGS. 10(A) and 10(B) are cross-sectional side views showing
a process for mounting the flow control structure of FIG. 8(B) onto
the cap of FIG. 9 according to another aspect of the present
invention;
[0020] FIG. 11 is a top plan view showing a process for securing
the flow control element of FIG. 8(B) to the cap of FIG. 9(B);
[0021] FIGS. 12(A) and 12(B) are cross-sectional side views showing
the non-spill beverage container of FIG. 6 during operation;
[0022] FIG. 13 is a perspective side view showing a non-spill
beverage container including a flow control structure according to
another exemplary embodiment of the present invention; and
[0023] FIGS. 14(A) and 14(B) are cross-sectional side views showing
a process for mounting the flow control structure onto the cap of
the non-spill beverage container of FIG. 13 according to another
aspect of the present invention.
DETAILED DESCRIPTION
[0024] FIG. 1 is a perspective view showing a flow control
structure 40 according to a generalized embodiment of the present
invention, and FIGS. 2(A) and 2(B) show flow control structure 40
in top plan and cross-sectional side views, respectively, where
FIG. 2(B) is taken along section line 2-2 of FIG. 2(A).
[0025] Flow control structure 40 includes a molded (first) member
50 including a tube-like spout 54 defining a substantially
cylindrical flow channel 56, a membrane 55 mounted on an upper
(first) end 54A of spout 54, and a baffle 65 mounted inside flow
channel 56 between upper end 54A and a lower end 54B of spout 54.
Spout 54 is a relatively rigid (i.e., compared to membrane 55)
tube-like structure extending generally along a central axis X
between upper end 54A and lower end 54B of spout 54. As indicated
in FIG. 2(A), in one embodiment spout 54 has a circular cross
section having an inner diameter (width) D1. In other embodiments,
spout 54 may have, for example, an oval, square or rectangular
cross section.
[0026] Membrane 55 is relatively elastic (i.e., compared to spout
54) and is connected to spout 54 adjacent to (i.e., at or slightly
inset from) upper end 54A such that membrane 55 is disposed across
fluid flow channel 56 to impede flow from fluid flow channel 56 and
an external region ER. In the disclosed embodiment, membrane 55 has
a circular outer perimeter 57 that is secured to upper end 54A of
spout 54. In one embodiment, elastic membrane 55 is formed from a
suitable material (e.g., soft rubber, thermoplastic elastomer, or
silicone) having a thickness T1 in the range of 0.01 to 0.1 inches
(more particularly 0.01 to 0.03 inches), and spout 54 is formed
from the same material and has a thickness T2 in the range of 0.05
to 0.12 inches. According to the present invention, membrane 55
defines a plurality of spaced-apart pinholes 59 formed using the
procedure describe below such that when membrane 55 is subjected to
normal atmospheric conditions (i.e., remains non-deformed),
pinholes 59 remain closed to prevent fluid flow between fluid flow
channel 56 and external region ER through membrane 55. As described
in additional detail below, pinholes 59 are also formed such that
when membrane 55 is deformed (stretched) in response to an applied
pressure differential between fluid flow channel 56 and external
region ER, pinholes 59 open to facilitate fluid flow through
membrane 55. Accordingly, pinholes 59 facilitate adjustable fluid
flow through membrane 55 that increases in direct relation to the
applied pressure differential, thereby facilitating the formation
of a non-spill beverage container.
[0027] As indicated in FIG. 2(B), according to an embodiment of the
present invention, membrane 55 is substantially flat (planar) in
its relaxed (i.e., non-deformed or unstretched) state, and lies in
a plane X-Y that is perpendicular to central axis X of flow channel
56. Two advantages are provided by making membrane 55 in this
manner. A first advantage, which is illustrated by the simplified
diagrams shown in FIGS. 3(A) and 3(B), is that a flat membrane is
easier to stretch under an applied pressure than a curved membrane.
In particular, as depicted in FIG. 3(A), a pressure P.sub.Z applied
perpendicular to substantially flat membrane 55 causes membrane 55
stretches (bows downward, as indicated by the dashed membrane 55').
Note that because membrane 55 is substantially flat, virtually all
of the resultant tensile force T generated in membrane 55 is
directed in the X-Y plane (indicated by component T.sub.X-Y),
thereby generating little or no component T.sub.Z in the Z-axis
direction until the membrane is at least partially stretched.
Because the tension component T.sub.Z remains relatively small,
planar membrane 55 is stretched (and the pinholes opened) in
response to a relatively small applied pressure P.sub.Z, thereby
facilitating fluid flow through membrane 55 in response to a
relatively small sucking force. In contrast, as indicated in FIG.
3(B), a pre-curved membrane 310 generates a significantly larger
tensile force component T.sub.Z, thereby requiring a substantially
larger pressure P.sub.Z to produce even a minimal stretching of
membrane 310 from its resting position (e.g., as indicated by
deformed membrane 310', shown in FIG. 3(B)). A second advantage to
provided by making membrane 55 substantially flat is that, as
described below, formation of the pinholes is greatly simplified
and facilitated.
[0028] Although the preferred embodiment includes a substantially
flat (planar) membrane, a curved membrane may also be used,
although such membrane would necessarily be relatively thin (i.e.,
relative to a flat membrane formed from the same material) in order
to facilitate a similar amount of deformation in response to an
applied pressure. A problem posed by using a relatively thin
membrane is the increased chance of rupture and/or tearing of the
membrane material, which may result in the unintended ingestion of
membrane material.
[0029] Referring to FIG. 2(A), according to an aspect of the
present invention, membrane 55 defines a plurality of spaced-apart
pinholes 59 that are arranged in a two-dimensional pattern. The
term "spaced-apart" is used to indicate that the pinholes are
separated by regions of non-perforated membrane material (i.e.,
there are no holes, cracks, slits, or other significant structural
weaknesses in the membrane material in the regions separating
adjacent pinholes). The spacing between pinholes 59 is selected
based on the membrane material such that tearing of the membrane
material between adjacent pinholes is avoided under normal
operating conditions (i.e., the pinholes are spaced as far apart as
is practical). Note that arranging pinholes 59 in a two-dimensional
pattern provides the advantage of balancing the distribution of
forces across membrane 55, thereby reducing the chance of tearing
of the membrane material.
[0030] According to an aspect of the present invention, spout 54
has a greater rigidity than the membrane 55 such that, when an
applied pressure differential is generated between fluid flow
channel 56 and external region ER, membrane 55 undergoes a greater
amount of deformation than spout 54. In one embodiment, membrane 55
and spout 54 are integrally connected to form an single-piece
member 50, which is molded from a suitable material (i.e., both
spout 54 and elastic membrane 55 are molded in the same molding
structure using a single molding material, e.g., silicone, a
thermoplastic elastomer, or soft rubber), and the increased
rigidity is provided by forming spout 54 to include a thickness T1
that is greater than the thickness T2 of membrane 55. In an
alternative embodiment, spout 54 may be formed at least partially
from a relatively rigid material (e.g., a hard plastic), and
membrane 55 may be separately formed from a relatively elastic
material and then secured to wall member 54. One example of this
arrangement is described below with reference to the disclosed
specific embodiment.
[0031] Referring again to FIGS. 1 and 2(A), membrane 55 is depicted
as being secured around its peripheral edge 57 to upper end 54A of
spout 54. Alternatively, membrane 55 may be recessed into flow
channel 56 to avoid damage caused, for example, by gumming or
chewing on the end of flow control structure 40, provided membrane
55 is positioned between baffle 65 and external region ER. However,
significantly recessing membrane 55 creates an open upper region
between the end of flow channel 56 (i.e., upper end 54A of
straw-like spout 54) that may undesirably create a reservoir for
small amounts of liquid that can drip after each sip, as described
above with respect to conventional non-spill beverage
containers.
[0032] In accordance with another aspect of the present invention,
several pinholes 59 are formed in membrane 55 to facilitate liquid
flow from flow channel 56 to external region ER in response to an
applied pressure differential (e.g., an applied suction). As
indicated in FIG. 4(A), each pinhole 59 is formed by piercing
membrane 55 with a pin 410, or other sharp pointed object, such
that the pinhole is closed by the surrounding elastomeric material
when pin 400 is subsequently removed. In a preferred embodiment,
membrane 55 is stretched in a radial direction by a force F that is
sufficient to increase the diameter of membrane 55 in the range of
1 to 10 percent during the formation of pinholes 59. When the
stretching force F is subsequently removed (i.e., membrane 55
returns to an unstretched state), pinholes 59 are collapsed by the
surrounding membrane material to provide a reliable seal. In
accordance with another aspect, each pin 410 is formed with a
continuously curved (e.g., circular) cross section such that each
pinhole 59 is substantially circular (i.e., does not have a slit or
fold that would be formed by a cutting element having an edge). In
one embodiment, pin 410 has a diameter in the range of 0.020 and
0.065 inches. Note that a pin having a diameter DIA of
approximately 0.063 inches was used in a punch (8 mm depth on
press) to produce successful pinholes in a membrane having a
thickness of approximately 0.02 inches. The number of pinholes 59
and membrane thickness T3 determine the amount of liquid flow
through membrane 55 during use for a given pressure differential,
as discussed below. During operation, as described in additional
detail below, membrane 55 is positioned between a liquid beverage
(not shown) and an external region. While atmospheric equilibrium
is maintained (i.e., the pressure on both sides of membrane 55 is
essentially equal), membrane 55 remains in the unstretched state
illustrated in FIG. 4(A), wherein pinholes 157 remain closed to
prevent leakage. During subsequent use (e.g., when a child sucks on
spout 54 like a straw), a pressure differential is generated in
which a relatively high pressure on the liquid side of membrane 55
becomes greater than the relatively low pressure on the suction
side, thereby causing membrane 55 to stretch outward, as indicated
in FIG. 4(B). The stretching of membrane 55 causes pinholes 59 to
open, thereby allowing the liquid beverage to pass therethrough.
Subsequently, when the pressure differential is relieved (i.e., the
child stops sucking), membrane 55 then returns to its unstretched
state, and pinholes 59 return to the closed state shown in FIG.
4(A). Note that because pinholes 59 do not include slits that can
become weakened and/or trap deposits that can prevent slit flap
closure, the flow control structure of the present invention
facilitates leak-free operation that is substantially more reliable
than that of conventional, slit-based flow control members.
[0033] Baffle 65 is an annular structure located inside flow
channel 56 and spaced from membrane 55 such that an upper (first)
flow channel region 56A is defined between baffle 65 and membrane
55, and a lower (second) flow channel region 56B is located on a
side of baffle 65 that is opposite to membrane 55 (e.g., between
baffle 65 and a beverage reservoir). Flow channel regions 56A and
56B communicate through opening 67, which has a relatively small
diameter D2 (FIG. 2(A)). In one embodiment, baffle 65 is a
substantially disk-shaped structure that is parallel to membrane 55
(when in its substantially planar, unstretched state), and opening
67 is aligned with the central axis X defined by spout 54. In
alternative embodiments baffle 65 is either integrally connected to
spout 54 and membrane 55 (i.e., formed as part of first member 50,
as depicted in FIG. 2(B)), or fabricated separately from a second
material (e.g., a rigid plastic), and inserted into flow channel
56, such as described below with reference to the disclosed
specific embodiment.
[0034] FIGS. 5(A) and 5(B) are cross-sectional side views showing a
simplified beverage container 500 including flow control structure
40 during operation. Beverage container 500 includes a container
body 510 having an outer wall 511 defining a beverage storage
chamber 517 containing a liquid beverage BVG, and an opening 519.
Flow control structure 40 is mounted over open end 519 such that
flow channel section 56B communicates directly with chamber 517 via
open end 519, and baffle 65 is positioned between chamber 517 and
flow channel section 56A. FIG. 5(A) shows beverage container 500 in
an inverted position prior to use (i.e., such that atmospheric
pressure is applied to the outside surface of membrane 55, and
beverage BVG is prevented from leaking out of container 500 solely
by flow control structure 40), and FIG. 5(B) shows beverage
container 500 while a suction is applied to flow control structure
40 by an external body 530 (e.g., a child's mouth). In one
embodiment, as indicated in FIG. 5(B), spout 54 and baffle 65
respectively have a greater rigidity than membrane 55 such that,
when the applied pressure differential is generated between fluid
flow channel 56 and external region ER (e.g., inside external body
530), membrane 55 undergoes a greater deformation than spout 54 and
baffle 65 in order to, for example, prevent collapse of flow
control element 40 during use.
[0035] According to another aspect of the present invention, baffle
65 and membrane 55 combine to further enhance the no-drip/non-spill
characteristic of flow control structure 40. First, the inventor
discovered that providing baffle 65 in flow channel 56 limits the
static pressure transmitted to membrane 55 while container 500 is
held in the inverted position indicated in FIG. 5(A). More
specifically, the inventor discovered that placing baffle 65 into
flow channel 56 allowed the inventor to increase the flow rate
characteristics of membrane 55 (e.g., reduce the thickness of
membrane 55 and/or increase the size of pinholes 59), making
membrane 55 more suitable for high volume flow, without increasing
the tendency for membrane 55 to leak in the inverted position. The
inventor currently believes that this beneficial characteristic may
be produced, at least in part, by a combination of baffle 65 acting
to limit the static pressure transferred to flow channel region 56A
from chamber 517, and by surface tension of beverage BVG in and
around opening 67. A second benefit of baffle 65 is that it impedes
relatively high pressure spikes in flow channel region 56A that are
generated, for example, when beverage container 500 is shaken up
and down or dropped while in the inverted position shown in FIG.
5(A). The inventors discovered that, when combined with a membrane
that exhibits leakage in response to such pressure spikes in the
absence of baffle 65, the presence of baffle 65 significantly
reduced and/or eliminated leakage through membrane 55, even when an
associated beverage container is shaken vigorously. As a third
benefit, referring to FIG. 5(B), when subsequently subjected to
suction by external body 530, the relatively high static pressure
differential creates liquid flow through membrane 55 that appears
to be minimally impeded by baffle 65. Accordingly, the inventor
found that by combining the increased flow rate characteristics of
membrane 55 with baffle 65, flow control structure 40 provides
superior non-spill, no-drip characteristics, compared to
conventional non-spill designs. Further, membrane 55 operates as
described above to automatically adjust the fluid flow rate through
flow control structure 40 to the applied suction, and to avoid the
clogging and tearing problems associated with conventional
slit-type elastic flow control structures.
[0036] The present invention will now be described with reference
to a specific embodiment.
[0037] FIG. 6 is a side view showing a non-spill beverage container
600 that utilizes a flow control structure 640 formed in accordance
with another specific embodiment of the present invention.
Container 600 generally includes a hollow cup-shaped body 610, and
a cap 620 having flow control structure 640 mounted thereon. Body
610 includes a roughly cylindrical sidewall 611 having a threaded
upper edge 613, and a bottom wall 615 located at a lower edge of
sidewall 611. Sidewall 611 and bottom wall 615 define a beverage
storage chamber 617 in which a beverage is received during use. Cap
620 includes a base portion 622 having threaded inside surface that
mates with threaded upper edge 613 to connect cap 620 to body 610,
and an upper wall 625 mounted on an upper edge of base portion 622
that combines with body 610 to substantially enclose storage
chamber 617. Upper wall 625 defines an outlet passage 626 and a
vent hole 627. Provided at a lower surface of upper wall 625 is a
cylindrical mounting structure 629 to which flow control structure
640 is secured. Note that cylindrical mounting structure 629
surrounds outlet passage 626 and vent hole 627.
[0038] According to the specific embodiment, flow control structure
640 includes an outer (first) member 650 that is mounted over an
inner (second) member 660. Outer member 650 is molded from a
relatively flexible elastomeric material (e.g., soft rubber,
thermoplastic elastomer, or silicone), and inner member 660 is
molded from a relatively rigid, food-safe plastic material (e.g.,
polypropylene). Outer member 650 includes a disk-shaped base 652
defining a vent structure 653, a tube-like outer spout portion 654
connected at its lower end 654B to base 652 and extending upward at
an angle from base 652, and a membrane 655 mounted across an upper
end 654A of outer spout portion 654. Vent structure 653 is a domed
protrusion that extends downward from disk-shaped base 652, and
includes a slit (not shown) that, similar to conventional valve
structures, opens in response to relatively low air pressure inside
beverage chamber 617 caused by beverage being drawn (sucked)
through flow control structure 640. Inner member 660, which is
shown in additional detail in FIGS. 7(A) and 7(B), includes a
disk-shaped base 662 that defines a vent hole 663 and includes a
thread 662T formed on its peripheral edge, a tube-like inner spout
portion 664 extending upward at an angle from base 662 and defining
an oval flow channel 666 having a minimum width W1 and a maximum
width W2, and a baffle 665 mounted in spout 664 between an upper
end 664A and a lower end 664B. As in the general embodiment
described above, flow channel 666 is separated into two regions
666A and 666B by baffle 665, with lower flow channel region 666B
communicating with beverage storage chamber 617. In one embodiment,
disk-shaped base has a diameter D11 of approximately one inch, oval
passage has a width W2 of approximately 0.4, respectively, and
opening 667 formed in baffle 665 has a diameter D12 of
approximately 0.01 to 0.1 inches. Note that disk-shaped base 652
has a diameter that is slightly smaller than diameter D11.
[0039] FIGS. 8(A) and 8(B) are cross-sectional side views showing a
process of assembling flow control structure 640. FIG. 8(A) shows
outer member 650 positioned over inner member 660 such that upper
end 664A of inner spout portion 664 is positioned for insertion
into an opening 656 defined by outer spout portion 654. Valve
member 650 is then pressed over spout 654 until a lower surface of
base 652 rests on an upper surface of base 662, and membrane 655
presses against upper end 664A of inner spout portion 664, with
slit-like vent extending through vent opening 663. As indicated in
FIG. 8(B), membrane 655 defines several normally-closed pin-holes
659 that are formed and function as described above with reference
to pin-holes 59.
[0040] FIG. 9 is a top plan view showing cap 620 in additional
detail. Outlet passage 626 is a curved opening that extends
partially around the circumference of cylindrical mounting
structure 629 (indicated with dashed lines), which extents from the
bottom side of wall 625. Vent hole 627 is also located inside the
circumference of cylindrical mounting structure 629.
[0041] FIGS. 10(A), 10(B) and 11 depict a process for mounting flow
control structure 640 onto cap 620. As shown in FIG. 10(A), flow
control structure 640 is positioned below wall 625 of cap 620 such
that membrane 655 is positioned under outlet passage 626. Flow
control structure 640 is then pushed upward such that spout 654/664
passes through outlet passage 626 until threads 662T formed on the
outer edge of disk-shaped base 662 engage matching threads formed
on the inside surface of cylindrical mounting structure 629. As
indicated in FIG. 11, with spout 654/664 protruding from upper wall
625 and positioned at the leftmost edge of outlet passage 626
(indicated by dashed line structure 640A), flow control structure
640 is then screwed/secured onto cylindrical mounting structure 629
by manipulating (sliding) spout 654/664 along outlet passage 626 to
its rightmost edge (as indicated by solid line structure 640B),
thus causing threads 662T of disk-shaped base 662 to screw into
cylindrical mounting structure 629 and to press base 652 against
the lower surface of wall 625, thus providing a reliable seal. Note
that, when flow control structure 640 is in the "locked" position
(i.e., represented by solid line structure 640B in FIG. 11), vent
hole 627 aligns with vent structure 653 (as indicated in FIG.
10(B)) thereby facilitating pressure equalization during use.
[0042] FIGS. 12(A) and 12(B) are cross-sectional side views showing
the non-spill beverage container 600 when at least partially filled
with a liquid beverage BVG). FIG. 12(A) shows non-spill beverage
container 600 in a tipped position whereby beverage BVG is able to
flow to membrane 655 by way of lower flow channel region 666B,
opening 667 formed in baffle 665, and upper flow channel region
666A. As described above with reference to the generalized
embodiment, baffle 665 and membrane 655 combine to prevent leakage
when a user is not applying suction to the end of spout 654/664.
When suction is applied by a user (not shown), the applied pressure
differential causes membrane 655 to bend outward to open pinholes
659 in the manner described above. As beverage BVG is drawn by the
user through spout 654/664, the resulting vacuum generated in
storage chamber 617 is equalized by way of vent hole 627 and vent
structure 653.
[0043] In accordance with another benefit of the present invention,
as indicated in FIG. 12(B), because membrane 655 is located at the
end of spout 654/664, when a user finishes drinking and membrane
655 closes, beverage that may be retained in upper flow channel
region 656A is prevented from dripping or otherwise discharging
from spout 654/664, thus avoiding the dripping problem associated
with conventional non-spill beverage containers.
[0044] FIG. 13 is a perspective side view showing a non-spill
beverage container 700 in accordance with another specific
embodiment of the present invention. Container 700 generally
includes a hollow cup-shaped body 710, and a cap 720 having flow
control structure 740 mounted thereon. Similar to the previous
embodiment, body 710 is a cup-shaped structure including a roughly
cylindrical sidewall having a threaded upper edge.
[0045] As shown in FIGS. 14(A) and 14(B), cap 720 includes a base
portion 722 having a threaded surface that mates with body 710, and
an upper wall 725 mounted on an upper edge of base portion 722 that
combines with body 710 to substantially enclose a beverage storage
chamber. Upper wall 725 defines an outlet passage 726 and a vent
hole (not shown). Provided at a lower surface of upper wall 725
around outlet passage 726 is a cylindrical mounting structure
(wall) 729, which includes a lip structure 729L formed on an inside
surface of cylindrical mounting structure 729 to which flow control
structure 740 is secured as described below.
[0046] Flow control structure 740, which is also shown in FIGS. 13
and 14, includes an outer (first) member 750 that is mounted over
an inner (second) member 760. Outer member 750 is molded from a
relatively flexible elastomeric material (e.g., soft rubber,
thermoplastic elastomer, or silicone), and inner member 760 is
molded from a relatively rigid, food-safe plastic material. Outer
member 750 includes a disk-shaped base 752 defining a vent
structure (not shown), a tube-like outer spout portion 754
connected at its lower end to base 752 and extending upward from
base 752, and a membrane 755 mounted across an upper end of outer
spout portion 754. Inner member 760 includes a disk-shaped base 762
that defines a vent hole (not shown), a tube-like inner spout
portion 764 extending upward from base 762 and defining a flow
channel 766, and a baffle 765 mounted between an upper end and a
lower end of spout 764. As in the general embodiment described
above, flow channel 766 is separated into two regions by baffle
765, with the lower flow channel region communicating with the
beverage storage chamber (not shown).
[0047] FIGS. 14(A) and 14(B) illustrate a process for mounting flow
control structure 740 onto cap 720. As shown in FIG. 14(A), flow
control structure 740 is positioned below wall 725 of cap 720 such
that membrane 755 is positioned under outlet passage 726. Flow
control structure 740 is then pushed upward (i.e., in the direction
of the dashed-line arrow) such that spout 754/764 passes through
outlet passage 726 until the peripheral edge of disk-shaped base
762 engages (i.e., is snap-coupled to) lip structure 729L formed on
the inside surface of cylindrical mounting structure 729, as
indicated in FIG. 14(B). An advantage of this embodiment is that it
avoids the need to turn (screw) flow control structure 740 relative
to cap 720, thereby simplifying the mounting procedure and
eliminating the elongated groove needed in the previous
embodiment.
[0048] In addition to the general and specific embodiments
disclosed herein, other features and aspects may be added to the
novel flow control structures that fall within the spirit and scope
of the present invention. For example, outer members 650/750 of
flow control structures 640/740 (described above) may omit base
652/752, and instead rely on another mechanism to secure membranes
655/755 to inner spout portion 664/764. The disclosed single-hole
baffle structure may be replaced with a multi-holed baffle, or any
baffle structure that defines at least one opening for permitting
fluid flow, but limits dynamic pressure changes in the flow channel
in the manner described herein. In addition, the disclosed
cylindrical mounting structures may be a shape other than
cylindrical, and base 662/762 may be removably attached to the
mounting structure by a mechanism other than the disclosed threaded
or snap-coupled connection, thereby removing the need for the
elongated passage 626/726. Further, the disclosed spout structures
may extend at an angle from hte respective base other than that
depicted (e.g., perpendicular to upper wall 625/725). In another
alternative embodiment, a cap may be formed that integrated the
inner spout portion. Moreover, while the present invention works
best with the pinhole membrane valve described herein, it may be
possible to replace the pinhole membrane structure with another
valve structure that, when combined in series with a baffle,
produces at least some of the beneficial characteristics described
herein. Therefore, the invention is limited only by the following
claims.
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