U.S. patent application number 12/136590 was filed with the patent office on 2008-10-02 for injection bonded articles and methods of fabrication and use thereof.
This patent application is currently assigned to SIEMENS WATER TECHNOLOGIES CORP.. Invention is credited to Li-Shiang Liang, Emile O. Montminy.
Application Number | 20080237045 12/136590 |
Document ID | / |
Family ID | 33299069 |
Filed Date | 2008-10-02 |
United States Patent
Application |
20080237045 |
Kind Code |
A1 |
Montminy; Emile O. ; et
al. |
October 2, 2008 |
INJECTION BONDED ARTICLES AND METHODS OF FABRICATION AND USE
THEREOF
Abstract
Injection bonded articles comprised of a rigid core and secured
together with an elastomeric material network which also forms
seals and encapsulates at least a portion of the rigid core. The
elastomeric material is selected to be compatible with the material
comprising the rigid core to create a chemical and mechanical bond
therebetween. Injection bonding and over-molding techniques are
used to fabricate an electrodeionization apparatus spacer comprised
of mated rigid segments secured by a unitary elastomeric material
network that also forms internal and external seals that fluidly
isolate one or more of inlet ports, resin cavities, and outlet
ports as well as throughports. Injection bonding and over-molding
techniques can also be used to fabricate other articles comprised
of multiple segments.
Inventors: |
Montminy; Emile O.;
(Harpswell, ME) ; Liang; Li-Shiang; (Harvard,
MA) |
Correspondence
Address: |
LOWRIE, LANDO & ANASTASI, LLP
ONE MAIN STREET, SUITE 1100
CAMBRIDGE
MA
02142
US
|
Assignee: |
SIEMENS WATER TECHNOLOGIES
CORP.
Warrendale
PA
|
Family ID: |
33299069 |
Appl. No.: |
12/136590 |
Filed: |
June 10, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10423245 |
Apr 25, 2003 |
7404884 |
|
|
12136590 |
|
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Current U.S.
Class: |
204/554 ; 24/304;
277/316 |
Current CPC
Class: |
B29L 2031/3431 20130101;
B01D 63/081 20130101; B29C 70/845 20130101; B29L 2031/26 20130101;
B29L 2031/3468 20130101; B01D 61/48 20130101; B29K 2101/10
20130101; B29L 2031/14 20130101; B01D 2313/44 20130101; B29C
45/14344 20130101; B29C 45/0062 20130101; Y10T 24/33 20150115; B01D
2313/143 20130101; B01D 61/50 20130101; B29C 45/14467 20130101;
B01D 63/084 20130101 |
Class at
Publication: |
204/554 ; 24/304;
277/316 |
International
Class: |
B01D 35/06 20060101
B01D035/06 |
Claims
1.-23. (canceled)
24. A filter cartridge comprising a filter element supported
between mating segments and a unitary elastomeric material network
within the mated rigid segments and forming a seal disposed around
at least a portion of a periphery of the mating segments.
25. The filter cartridge of claim 24, further comprising a sheath
comprised of the unitary elastomeric material and encapsulating at
least a portion of an outer periphery of the mating segments.
26. A method of fabricating an electrodeionization apparatus spacer
comprising: providing a first segment and a second segment, the
first and second segments having complementary features that allow
mating assembly of the first and second segments in a predetermined
arrangement; mating the first and second segments to form a rigid
core comprising a channel traversing at least a portion of an
interface between the first and second segments and a resin cavity
in communication with an inlet port and an outlet port; and
injecting an elastomeric material into the channel to form an
elastomeric network between the first and second segments.
27. The method of claim 26, further comprising a step of
encapsulating at least a portion of the mated first and second
segments with the elastomeric material.
28. The method of claim 26, further comprising a step of forming a
seal at a periphery of the mated first and second segments with the
elastomeric material.
29. The method of claim 26, further comprising a step of forming a
resin cavity seal around the resin cavity with the elastomeric
material.
30. The method of claim 26, further comprising a step of forming an
inlet port seal around the inlet port with the elastomeric
material.
31. The method of claim 26, further comprising a step of forming an
outlet port seal around the outlet port with the elastomeric
material.
32. The method of claim 26, further comprising a step of forming an
internal inlet seal with the elastomeric material at the interface
and around an inlet manifold that fluidly connects the inlet port
to the resin cavity.
33. The method of claim 26, further comprising a step of forming an
internal outlet seal with the elastomeric material at the interface
and around an outlet manifold that fluidly connects the resin
cavity to the outlet port.
34. The method of claim 26, further comprising a step of forming a
through port seal with the elastomeric material around a through
port defined in the mated first and second segments, the through
port seal fluidly isolates the through port from the inlet port,
the outlet port, and the resin cavity.
35. The method of claim 26, further comprising a step of forming an
internal seal with the elastomeric material at the interface, the
internal seal fluidly isolates the inlet port from the outlet
port.
36. The method of claim 26, wherein the first and second segments
and the elastomeric material are comprised of a thermoplastic
polymer.
37. A method of fabricating an electrodeionization apparatus spacer
comprising: mating a first complementary rigid segment to a second
complementary rigid segment to form a rigid core comprising a resin
cavity in communication with an inlet port and an outlet port; and
binding the first and second complementary segments with an
elastomeric material.
38. The method of claim 37, further comprising a step of forming a
seal with the elastomeric material on an outer surface of the mated
first and second complementary segments.
39. The method of claim 38, further comprising a step of forming an
inlet port seal with the elastomeric material around the inlet
port.
40. The method of claim 40, further comprising a step of forming an
outlet port seal with the elastomeric material around the outlet
port.
41. The method of claim 40, further comprising a step of
encapsulating at least a portion of a surface of the mated first
and second complementary segments with the elastomeric
material.
42. The method of claim 41, further comprising a step of forming an
internal inlet seal with the elastomeric material at the interface
and around an inlet manifold that fluidly connects the inlet port
and the resin cavity.
43. The method of claim 42, further comprising a step of forming an
internal outlet seal with the elastomeric material at the interface
and around an outlet manifold that fluidly connects the outlet port
and the resin cavity.
44. A method of assembling an electrodeionization apparatus
comprising positioning a depleting compartment spacer into an
electrodeionization apparatus assembly, wherein the depleting
compartment spacer is comprised of a rigid core and an elastomeric
material seal disposed within the rigid core.
45. A method of purifying water comprising: introducing water to be
purified into an electrodeionization apparatus comprising a
concentrating compartment defined by a concentrating compartment
spacer and a depleting compartment disposed adjacent the
concentrating compartment and defined by a depleting compartment
spacer comprising a rigid core and an elastomeric material network
disposed within the rigid core; and applying an electrical
potential across the electrodeionization apparatus to promote
migration of undesirable species in the water from the depleting
compartment into the concentrating compartment.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to injection bonded components and
methods thereof and, more particularly to electrically driven
purification apparatus comprising injection bonded components.
[0003] 2. Discussion of Related Art
[0004] The fabrication of articles having a rigid part and an
elastomeric part has been described. For example, Kaufman, Jr. et
al., in U.S. Pat. No. 3,398,222, describe a method of making wheel
comprised of a plastic material and a rubber material by molding a
continuous rubber body to a rigid plastic body. Smith, in European
Patent Application Publication 0 600 187, describes a composite for
in-mould transfer printing and the decoration of plastic or rubber
articles as well as a process for their use. Gee et al., in
International Publication Number WO 96/18550, describe bonding a
cured elastomer to a component made of plastic and metal by
ionizing a surface of the elastomer and ionizing a surface of the
plastic and then compressing the ionized surfaces together while
applying pressure and heat.
[0005] Tensor, in U.S. Pat. No. 5,700,017, describes a flanged
rubber combustion seal. An elastomeric combustion seal for a
cylinder head gasket of an internal combustion engine includes a
radially inner sealing section and a radially outer section. A
first integral cantilevered section is disposed between the inner
sealing section while a second integral cantilevered section
extends radially outwardly from the outer section and is bonded to
an inner peripheral edge of a base plate. The seal has grooves with
roots.
[0006] The purification and/or treatment of liquids has been
described. For example, McMahon, in U.S. Pat. No. 5,166,220,
describes a water softening process wherein a brine solution is
used for the regeneration of ion exchange resin. Other systems that
can be used to purify or demineralize water have also been
described. For example, Gaysowski, in U.S. Pat. No. 3,407,864,
describes an apparatus that involves both ion exchange and
electrodialysis. Johnson, in U.S. Pat. No. 3,755,135, describes a
demineralizing apparatus using a DC potential. Also, Brattan, in
U.S. Pat. No. 4,832,804, describes an electrolytic cell that has
electrodes, an inlet channel, and an outlet channel.
[0007] Electrodeionization devices can also be used to purify water
as described by, for example, Giuffrida et al. in U.S. Pat. Nos.
4,632,745, 4,925,541 and 5,211,823, by Ganzi in U.S. Pat. Nos.
5,259,936 and 5,316,637, by Parsi et al. in U.S. Pat. No.
5,066,375, by Oren et al. in U.S. Pat. No. 5,154,809 and by Kedem
in U.S. Pat. No. 5,240,579.
[0008] Components, and methods thereof, of such electrically driven
apparatus have also been described. For example, Guerif, in U.S.
Pat. No. 4,999,107, describes a separator frame for a two-fluid
exchanger device and a seal plane obtained by assembling four
thermoplastic sheets about a screen, wherein the outermost sheets
is flexible, and hollowed-out in zones corresponding to diffusers.
Guerif, in U.S. Pat. No. 5,185,048, describes manufacturing a
separator frame for a stack in an exchanger device. The separator
is made by assembling two thermoplastic films having the shape of a
seal plane and sandwiched over two different types of thermoplastic
expanded structures. Goldstein, in U.S. Pat. No. 5,891,328,
describes a membrane-frame for processes including electrodialysis.
The integral, monolithic frame-membrane has a semi-permeable
membrane portion and a frame portion. Sato et al., in U.S. Pat. No.
6,402,920, describe a concentrating compartment and spacer
construction for an electrodeionization apparatus. The spacer is
composed of a mesh and a frame-shaped gasket superposed on the
periphery of the mesh. Further, Agarwal et al., in U.S. Pat. No.
5,295,698, describe a molded plastic gasket that has a main body
and an integrally formed sealing bead surrounding a service
opening. The sealing bead is vertically moveable relative to the
gasket body.
[0009] Steck et al., in U.S. Pat. No. 5,464,700, describe a
gasketed membrane electrode assembly for electromechanical fuel
cells. The gasketed membrane electrode assembly uses gasketing
material at the periphery of an ion exchange membrane. Merida, W.
R. et al., in "Novel PEM Fuel Cell Design with Non-Planar
Membrane-Electrode Assemblies," 10.sup.th Canadian Hydrogen
Conference, pp. 745-753, Quebec, 2000, describe a proton exchange
membrane fuel cell design based on a non-planar electrode-membrane
assembly and non-conventional collector plates.
BRIEF SUMMARY OF THE INVENTION
[0010] The present invention is directed to injection bonded
components and methods thereof and, in one or more embodiments, to
electrodeionization apparatus having injection bonded components
and methods of manufacturing and uses thereof.
[0011] In accordance with one or more embodiments, the present
invention provides an electrodeionization apparatus spacer
comprising a rigid core and an elastomeric material network within
the rigid core and forming a seal on at least a portion of a
surface of the rigid core. In some embodiments, the
electrodeionization apparatus spacer further comprises a resin
cavity in fluid communication with an inlet port and with an outlet
port, wherein the inlet port, the outlet port, and the resin cavity
are defined in the rigid core.
[0012] In other embodiments, the present invention provides an
electrodeionization apparatus spacer comprising a rigid core and a
unitary elastomeric material wherein a portion of the elastomeric
material forms a seal disposed within the rigid core and wherein a
portion of the elastomeric material encapsulates at least a portion
of an outer surface of the rigid core. In some embodiments, the
electrodeionization apparatus spacer further comprises an internal
outlet seal comprised of the elastomeric material and disposed
within the rigid core and/or an internal inlet seal comprised of
the elastomeric material and disposed within the rigid core.
[0013] In other embodiments, the present invention provides an
electrodeionization apparatus spacer comprising a rigid core
comprising an inlet port connected to a resin cavity through an
inlet conduit and an outlet port connected to the resin cavity
through an outlet conduit. The electrodeionization apparatus spacer
further comprises a unitary resilient material forming an inlet
port seal around the inlet port, a resin cavity seal around the
resin cavity, an outlet port seal around the outlet port, an inlet
conduit seal around the inlet conduit, an outlet conduit seal
around the outlet conduit and an outer seal disposed around a
periphery of the rigid core. In some embodiments, the rigid core
and the unitary resilient material is comprised of a thermoplastic
material.
[0014] In other embodiments, the present invention provides an
electrodeionization apparatus comprising a concentrating
compartment defined by a concentrating compartment spacer and a
depleting compartment disposed adjacent the concentrating
compartment. In some embodiments, the depleting compartment is
defined by a depleting compartment spacer comprised of a rigid core
and an elastomeric material network disposed within the rigid
core.
[0015] In other embodiments, the present invention provides a
method of fabricating an electrodeionization apparatus spacer
comprising a step of providing a first segment and a second
segment. In some embodiments, the first and second segments have
complementary features that allow mating assembly in a
predetermined arrangement. The method further comprises a step of
mating the first and second segments to form a rigid core
comprising a channel traversing at least a portion of an interface
between the first and second segments and a resin cavity in
communication with an inlet port and an outlet port. The method can
further comprise a step of injecting an elastomeric material into
the channel to form an elastomeric network between the first and
second segments. In some embodiments, the method further comprises
a step of forming an internal inlet seal with the elastomeric
material at the interface and around an inlet manifold that fluidly
connects the inlet port to the resin cavity and/or a step of
forming an internal outlet seal with the elastomeric material at
the interface and around an outlet manifold that fluidly connects
the resin cavity to the outlet port. In yet other embodiments, the
first and second segments and the elastomeric material are
comprised of a thermoplastic polymer.
[0016] In other embodiments, the present invention provides a
method of fabricating an electrodeionization apparatus spacer
comprising a step of mating a first complementary rigid segment to
a second complementary rigid segment to form a rigid core that
comprises or defines a resin cavity in communication with an inlet
port and an outlet port. In some embodiments, the method further
comprises a step of binding the first and second complementary
segments with an elastomeric material. In yet other embodiments,
the method further comprises a step of forming a seal with the
elastomeric material on an outer surface of the mated first and
second complementary segments.
[0017] In other embodiments, the present invention provides a
method of assembling an electrodeionization apparatus comprising a
step of positioning a depleting compartment spacer into an
electrodeionization apparatus assembly. In some embodiments, the
depleting compartment spacer comprises a rigid core and an
elastomeric material seal disposed within the rigid core.
[0018] In other embodiments, the present invention provides a
method of purifying water comprising a step of introducing water to
be purified into an electrodeionization apparatus comprising a
concentrating compartment defined by a concentrating compartment
spacer and a depleting compartment disposed adjacent the
concentrating compartment and defined by a depleting compartment
spacer that comprises a rigid core and an elastomeric material
network disposed within the rigid core. The method further
comprises a step of applying an electrical potential across the
electrodeionization apparatus to promote migration of undesirable
species in the water from the depleting compartment into the
concentrating compartment.
[0019] In other embodiments, the present invention provides a
filter cartridge comprising a filter element supported between
mating segments and a unitary elastomeric material network within
the mated rigid segments forming a seal disposed around at least a
portion of a periphery of the mating segments. In some embodiments,
the filter cartridge further comprises a sheath comprised of the
unitary elastomeric material encapsulating at least a portion of an
outer periphery of the mating segments.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0020] The accompanying drawings are not intended to be drawn to
scale. In the drawings, each identical or nearly identical
component that is illustrated in various figures is represented by
a like numeral. For purposes of clarity, not every component may be
labeled in every drawing. Preferred non-limiting embodiments of the
present invention will be described by way of example with
reference to the accompanying drawings, in which:
[0021] FIG. 1 is a perspective view of an article having two mating
segments according to one or more embodiments of the present
invention;
[0022] FIG. 2 is a cross-sectional view of the article of FIG. 1
showing the fabrication of the mating segments by injection bonding
with a material that is introduced between the segments according
to one or more embodiments of the present invention;
[0023] FIG. 3 is a cross-sectional view of an article showing the
fabrication of mating segments by injection bonding and
encapsulation with a material that is introduced between the
segments according to one or more embodiments of the present
invention;
[0024] FIG. 4 is a perspective view of an injection bonded article
having a sheathing according to one or more embodiments of the
present invention;
[0025] FIG. 5 is a cross-sectional view of an injection bonded
article showing an assembly of plastic parts bonded with an
elastomeric material which also encapsulates a portion of an outer
surface of the plastic components according to one or more
embodiments of the present invention;
[0026] FIG. 6 is an exploded view of an electrodeionization
apparatus spacer according to one or more embodiments of the
present invention;
[0027] FIG. 7 is an exploded view of an electrodeionization spacer
according to one or more embodiments of the present invention;
[0028] FIGS. 8A-8D are schematic illustrations of an injection
bonded kitchen article according to one or more embodiments of the
present invention;
[0029] FIG. 9 is a cross-sectional view of an in-line separation
device according to one or more embodiments of the present
invention;
[0030] FIG. 10 is a cross-sectional view of a portion of the
injection bonded article of FIG. 9;
[0031] FIGS. 11A-11D are schematic illustrations of injection
bonded articles according to one or more embodiments of the present
invention, wherein FIG. 11A is an exploded view of a disposable
camera having a rigid component comprised of an elastomeric
material and mating segments, FIG. 11B is a perspective view of the
fabricated disposable camera shown in FIG. 11A, FIG. 11C is a
perspective view of a sealed or sheathed electronic device, and
FIG. 11D is a perspective view of a sealed or sheathed rechargeable
flashlight;
[0032] FIG. 12 is a schematic illustration of an
electrodeionization apparatus spacer according to one or more
embodiments of the present invention;
[0033] FIG. 13 is a perspective view of an electrodeionization
apparatus utilizing the spacer illustrated in FIG. 12 according to
one or more embodiments of the present invention; and
[0034] FIG. 14 is a cross-sectional view of a seal utilized in the
spacer illustrated in FIG. 12 according to one or more embodiments
of the present invention;
[0035] FIG. 15 is a schematic view of a portion of a fuel cell;
and
[0036] FIG. 16 is an enlarged schematic view of the portion of the
fuel cell shown in FIG. 15.
DETAILED DESCRIPTION OF THE INVENTION
[0037] The present invention provides injection bonded articles and
methods of fabricating and uses thereof. The injection bonded
articles can comprise a plurality of rigid segments, which can be
mated in a predetermined and/or complementary arrangement. In some
embodiments, the articles typically comprise a plurality of
segments bonded or secured together with a material disposed at an
interface between adjoining or adjacent segments. In other
embodiments, the injected material can further form an
encapsulating sheath over at least a portion of a surface of the
rigid segments. Notably, the injected material can be used in
conjunction with over-molding techniques to form features or
structures on an outer and/or inner surface of the rigid segments.
The articles can further comprise internal features, such as but
not limited to, conduits or channels, without the use of cutting,
drilling, or other techniques requiring material loss or removal
such as the lost-wax or investment casting technique. Other
internal features or structures such as internal seals can also be
present. In other embodiments, the articles comprise
complementarily mating rigid segments having features, such as
indentations and protrusions that permit assembly in a
predetermined arrangement. The mated rigid segments typically
define or have channels, passageways, or pathways wherein a
flowable material can be induced to move therethrough during
fabrication of the injection bonded articles. Also during
fabrication, the flowable material can be induced on a surface,
such as an outer, exposed surface, of the mated rigid segments. The
flowable material, at least partially filling the channels defined
in the mated rigid segments can be induced to undergo a change,
such as a phase change by, for example, cooling, chemical reaction,
or both to form a network disposed within the rigid component and,
in some cases, at least partially on the surface of the mated rigid
segments forming the rigid component. In some embodiments, the
material filling the channels can further form structures disposed
internally in the rigid component. In yet other embodiments, the
flowable material can form a network of such material disposed
within the rigid component and, in still other embodiments, on at
least a portion of the outer surface of the rigid component.
Further embodiments contemplated within the scope of the present
invention include a rigid component comprises segments having a
network of material disposed therein as well as on a surface
thereof that define features, externally, internally, or both, such
that the material forms a unitary element.
[0038] In still other embodiments, the present invention provides
methods of fabricating a rigid plastic component having an
elastomeric material network disposed therein and partially
encapsulating at least a portion of an outer surface of the rigid
plastic component. The rigid component can comprise a plurality of
segments, i.e. two or three or more segments; and in some
embodiments, the rigid component can comprise a plurality of mated
rigid segments defining a core; and in yet other embodiments, the
rigid component can comprise a plurality of rigid segments having
features that permit their complementary mating in a predetermined
arrangement. The present invention can also provide an article
comprising a rigid component, such as a rigid core, comprising two,
three or more mated rigid plastic material segments and a network
comprised of an elastomeric material disposed between and-securing
together the mated plastic material segments. The article can
further comprise a sheathing comprised of the elastomeric material
disposed on at least a portion of an outer surface of the rigid
core. In some embodiments, the rigid plastic material and the
elastomeric material are comprised of a thermoplastic polymer.
[0039] Various techniques can be used to introduce the material and
promote filling and flow through the channels and further into
adjacent structures. For example, the material can be introduced by
transfer molding, wherein pressure is used to introduce the
material while closing an appropriate mold in which the rigid
segments are disposed. In other embodiments, the present invention
provides a method of fabricating an article. The method comprises
steps of providing a first segment and a second segment, the first
and second segments comprised of a rigid plastic material and
having complementary features that allow mating assembly of the
first and second segments in a predetermined arrangement and mating
the first and second segments to form a core comprising a channel
traversing at least a portion of an interface between the first and
second segments. The method can further comprise a step of
injecting an elastomeric material into the channel to form an
elastomeric material network between the first and second segments.
In some embodiments, the method can still further comprise a step
of forming a sheathing comprised of the elastomeric material on at
least a portion of an outer surface of the core.
[0040] According to one or more embodiments, the present invention
can utilize transfer molding, injection molding, compression
molding, reaction-injection molding, over-molding techniques, as
well as combinations thereof The present invention can be utilized
to fabricate articles comprised of any combination of plastic,
thermoplastic, thermosetting, as well as elastomeric or resilient
materials. In some embodiments, the present invention provides
assembly of rigid segments into a rigid core secured together with
an elastomeric material.
[0041] According to one or more embodiments of the present
invention, and as illustrated in FIG. 1, a first segment 100 and a
second segment 105 can have recessed structures 110 and 115 that
form or define channels or passages in or when segments 100 and 105
are assembled together in a complementary mating arrangement to
form, for example, a rigid component or core 120, also shown in a
cross-sectional view in FIG. 2. The first and second assembled
segments 100 and 105 can be placed in an apparatus that provides
for a compressive force or load and/or heating of the assembled
segments. The rigid segments can be heated in the mold assembly. A
material, typically a flowable material, can be introduced into the
channel defined by grooves 110 and 115 when segments 100 and 105
are assembled together to form mated rigid component 120.
[0042] For illustrative purposes only, the flowable material in
accordance with the present invention will be referred to as an
elastomeric material. The present invention fully contemplates
utilizing other similar materials. Such materials include
thermosetting materials, thermoplastic materials and blends,
copolymers, or mixtures thereof. Such material also includes
reactive materials that form crosslinking chemical bonds. The
elastomeric material typically flows at elevated temperatures and
flows under pressure but can become solid or non-molten at ambient
or low temperatures. The elastomeric material can become a solid,
non-flowing material as a result of a physical or chemical change
or reaction. For example, the elastomeric material can comprise a
thermosetting polymer material that can form crosslinking chemical
bonds between polymeric chains thereby transforming the physical
properties of the elastomeric material.
[0043] As shown in the embodiment depicted in FIG. 2, an
elastomeric material 210 can be introduced, shown generally by
arrows 212, into a gate, sprue or runner 214 defined in a mold
assembly 215, which is typically comprised of mold segments 200 and
205. Typically, elastomeric material 210 flows under pressure
and/or at elevated temperatures. The elastomeric material 210 can
further flow into a channel 216 defined in or between, for example,
mated segments 100 and 105, shown disposed in a mold cavity 206 and
defined by mold segments 200 and 205. The elastomeric material can
also fill cavities defined in the mated segments 100 and 105 to
form internally disposed structures (not shown).
[0044] In other embodiments of the present invention, the
elastomeric material 210 can be used to form or over-mold on mated
segments 100 and 105 to partially or completely encapsulate an
outer surface 220 of the rigid component 120. For example, as shown
in the cross-sectional view depicted in FIG. 3, rigid segments 100
and 105, which can be assembled in a predetermined fashion and
disposed in a mold cavity 206, defined by mold segments 200 and 205
in mold assembly 215. The mold assembly 215 having rigid segments
100 and 105 disposed therein can be heated to elevated temperatures
in an oven or by heated plattens of a press (not shown).
Elastomeric material 210 can be introduced into runners 214 defined
in one or both mold segments 200 and 205 by techniques including,
but not limited to transfer, injection, reaction and compression
molding. Elastomeric material 210 can enter into channel 216.
Elastomeric material 210 can be over-molded around an outer surface
220 of one or both mated segments 100 and 105 by flowing into and
through secondary channels 218, defined in one or both rigid
segments 100 and 105, and flow into a secondary cavity 222 to form
a sheathing structure 224 (shown in FIG. 4) when the elastomeric
material 210 cools to a solid. The secondary cavities 222 can
further provide complementarily-shaped features (not shown) such
that when elastomeric material 210 fills cavity 222, it conforms
and assumes the shape of the complementary features thereby
providing for structures formed on surface 220 of the rigid
component. For example, cavity 222 can be shaped to provide a seal
that can be formed on a surface of the rigid component. As shown in
FIG. 4, the present invention provides an injection bonded article
300 having mated rigid segments 100 and 105 and comprising a
sheathing 224 made of an elastomeric material, which can also form
a network disposed between the mated rigid segments. The
elastomeric material network and the sheathing can be formed as a
unitary structure.
[0045] According to some embodiments, the elastomeric material
comprises a thermoplastic elastomer material (TPE). In yet other
embodiments, the rigid segments are comprised of a thermoplastic
material. In still other embodiments, the thermoplastic material
and the rigid segments are comprised of a thermoplastic material
such as a thermoplastic elastomer material. For example, the TPE
and the mating segments may comprise a polyolefin polymer that can
be melted at processing temperatures. Thus, in accordance with one
or more embodiments of the present invention, molten TPE can be
introduced into in channels 216 and 218 at a temperature that can
melt, at least locally, the respective contacted, wetted surfaces
of mating segments 100 and 105. Once the TPE has at least partially
filled channels 216 and 218 and, optionally, cavities 222, the
assembly can be cooled and removed from mold assembly 215. Upon
cooling a thermal bond can be formed between the rigid segments,
the sheathing and the TPE forming the elastomeric material network
disposed between the rigid segments.
[0046] In accordance with one or more embodiments, the present
invention provides an electrodeionization apparatus spacer
comprising a rigid core and an elastomeric material network. The
elastomeric material network can be disposed within the rigid core.
In some embodiments, the elastomeric material can form a seal on at
least a portion of the surface of the rigid core. The elastomeric
material can further be formed into sealing structures, such as
seals, providing fluid isolation of structures defined in the rigid
core. The electrodeionization spacer can have one or more resin
cavities defined therein and which can be in fluid communication
with at least one of an inlet port and an outlet port, each also
defined in the rigid core. Other structures and features can also
be defined in or on the rigid core. For example, the rigid core can
further include throughports defined in the rigid core that can act
as a channel that can permit fluid communication through the rigid
core.
[0047] In some embodiments, one or more ports defined in the rigid
core can have at least one seal disposed at a periphery of the one
or more ports. For example, an inlet port seal can be disposed on a
surface of the rigid core around a periphery of an inlet port. In
some embodiments, the seal is comprised of an elastomeric material
and in other embodiments, the seal is comprised of the elastomeric
material that forms an elastomeric material network. The
electrodeionization spacer can include a peripheral seal disposed
on a surface of the rigid core.
[0048] In still other embodiments, the elastomeric material forms a
sheath that encapsulates, at least partially, a surface of the
rigid core. In yet other embodiments, the elastomeric material can
further define structures within the rigid core that seals and
fluidly isolates channels or other structures defined within the
rigid core. For example, the elastomeric material can define a
network that comprise seals fluidly isolating any one of the resin
cavities, the inlet or outlet ports, as well as any throughports
and manifolds, channels or conduits defined in the rigid core.
[0049] The elastomeric material can be any resilient material that
is physically and chemically compatible for use in the
electrodeionization apparatus. The elastomeric material can
comprise any material that is moldable at suitable processing
conditions. For example, the elastomeric material can comprise a
thermoplastic material, a thermosetting material or a combination
or blend thereof. Further, the elastomeric material can be a
chemical or mechanical blend of one or more thermoplastic or
thermosetting polymers. Examples of elastomeric materials that may
be suitable for use in electrodeionization apparatus include, but
are not limited to, polymers or copolymers of styrene, polyester,
polyurethane, polyamide and polyolefin.
[0050] FIG. 5 shows a cross-section of an assembly according to one
or more embodiments of the present invention. An injection bonded
article 305 shows an assembly of three plastic parts, or rigid
segments, bonded together with an elastomeric material which also
at least partially encapsulates an outer surface of the segments.
Rigid segments 315 and 320 can be secured together along with a
screen 325 sandwiched therebetween. An elastomeric material forms
an internal network 330 between rigid components 315 and 320 in
such a way that it can mechanically and/or chemically bond screen
325 between rigid segments 315 and 320. The elastomeric material
can also form a seal 310 on an outer surface of mated segments 315,
320, and 325. The elastomeric material can also partially
encapsulate the assembly to form a sheath 310.
[0051] In accordance with one or more embodiments of the present
invention, FIG. 6 shows an exploded view of an electrodeionization
apparatus spacer comprising a first section or segment 335 and a
second section or segment 340 that can mate in a complementary
arrangement to form a rigid core secured together with an
elastomeric material network 345. The electrodeionization apparatus
spacer can be fabricated by providing the first mating segment 335
which can be fabricated by techniques known in the art such as, but
not limited to, molding or machining a rigid material. Similarly,
second section 340 can be fabricated and provided in the same
manner. The electrodeionization apparatus spacer can be constructed
by disposing mating first and second segments 335 and 340 in an
appropriate mold (not shown) and injecting an elastomeric material
to form elastomeric material network 345 in internal structures,
such as channels 350, defined by the assembly of segments 335 and
340. The elastomeric material network can secure complementary
mating first and second segments 335 and 340. In some embodiments,
the complementary mating first and second sections as well as the
elastomeric material comprise a thermoplastic material.
[0052] The elastomeric material can comprise any resilient material
that is chemically and mechanically stable during use. In some
embodiments, the elastomeric material has a Shore A Hardness of
between about 40 to about 90, preferably from about 50 to about 80,
and more preferably from about 60 to about 75, as determined by
ASTM D 2240 or TPE 0169. In some embodiments, the elastomeric
material has a hardness property that is sufficient to allow
compression without significant material flow under pressure. In
some embodiments, the elastomeric material has a resistance to
compression set sufficient to prevent fluid from flowing
therethrough while under pressure. In yet other embodiments, the
rigid material and the elastomeric material are comprised of a
material that is suitable for use in food or pharmaceutical
applications. In some embodiments, the elastomeric material can
comprise a thermoplastic or thermosetting polymer that is flexible
relative to the rigid material during operation or use. Examples of
elastomeric materials include, but are not limited to, resilient
materials such as thermoplastic elastomer materials like styrene
block co-polymers, co-polyesters, polyurethane, polyamide,
polyolefin, and other thermoplastic or thermosetting polymers. An
example of a suitable elastomeric material includes, but not
limited to, SANTOPRENE.RTM. thermoplastic elastomer resins
available from Advanced Elastomer Systems, Akron, Ohio;
SOFTFLEX.RTM. thermoplastic elastomer resins available from Network
Polymers, Inc., Akron, Ohio; STARFLEX.RTM. thermoplastic elastomer
resins available from Star Thermoplastic Alloys & Rubber, Inc.,
Glen View, Ill.; VERSALLOY.RTM. XL9000 thermoplastic elastomer
resins, available from GLS Corporation, McHenry, Ill.;
MORTHANE.RTM. resins available from Rohm and Haas Company,
Philadelphia, Pa.; and ESTANE.RTM. thermoplastic polyurethane
resins available from The B.F. Goodrich Company, Cleveland, Ohio or
Noveon, Inc., Cleveland, Ohio. The elastomeric material can also
comprise reinforced, non-reinforced, filled or unfilled
thermosetting vulcanizates, or blends and mixtures thereof, such as
natural rubber as well as styrene-butadiene, polybutadiene,
ethylene/propylene, butyl, chlorobutyl, polyisoprene, nitrile,
polyacrylate, chloroprene, chlorosulfonated polyethylene,
polysulfide, silicone, and fluorocarbon polymers.
[0053] During fabrication, the elastomeric material can locally
melt, for example during molding, a portion of the rigid first or
second sections. Typically, upon cooling, the complementary mating
first and second sections are fused together or at least fused or
secured to the non-molten elastomeric material.
[0054] In other embodiments, the rigid core can comprise a material
that is sufficiently inflexible and can maintain its general shape
under force or pressure during use or service as in, for example,
an electrodeionization apparatus. The rigid material can comprise a
material that is resistant to stress relaxation and able to
withstand conditions during operation of an electrodeionization
apparatus. In some embodiments, the rigid material is electrically
insulating and chemically resistant to high or low pH liquids. In
yet other embodiments, the rigid material is inflexible relative to
the elastomeric material, is thermally stable, chemically
resistant, heat resistant, and dimensionally stable during use or
in service. Other properties that may be relevant to determining
applicability includes, but is not limited to, the mechanical
properties, such as rigidity, impact resistance, surface quality,
wear resistance; chemical properties, such as flame retardance,
conductivity, compatibility, and weight; dielectric; weathering;
and processing properties, as well as cost and availability of the
material. The rigid material can be fabricated from any suitable
material such as, but not limited to, thermoplastic, thermosetting,
or blends or copolymers of polymeric materials, as well as metals,
or combinations or alloys thereof, so long as it is suitable for
its intended use. In some embodiments, the rigid material is
comprised of a reinforced thermoplastic or thermosetting material.
For example, the rigid material can be reinforced by compounding,
blending, fibers and/or minerals in a polymeric matrix. Examples of
other suitable reinforcing fillers include, but are not limited to,
glass fibers, aramid fiber, silica, and carbon black. Examples of
suitable polymeric materials include, but are not limited to
polypropylene, polyethylene, polycarbonate, nylon,
polyacryletherketone, styrene-acrylonitrile, cyclic olefin
copolymer, polyimide, polysulfone, polyphenylsulfone, polyphenylene
oxide, polyphenylene ether, chlorinated poly(vinyl chloride),
polyphenylene sulfide, polyetherimide, polyetherketone, polyamide,
polyimide, polybenzimidazole, and polystyrene, as well as blends,
copolymers, or mixtures thereof. The rigid segments can also
comprise a thermosetting polymeric material such as, but not
limited to, epoxy, urethane, and phenol, as well as blends or
copolymers thereof. Suitable commercially available material
includes RADEL.RTM. polyphenylsulfone resins available from Solvay
Engineered Polymers, Auborn Hills, Mich. as well as NORYL.RTM.
polyphenylene-based resins available from GE Plastics, Pittsfield,
Mass.
[0055] Selection of suitable rigid material/elastomeric material
sets depend on several factors including those relevant to
fabrication, cost, and conditions in use. For example, at least one
of the rigid segments comprises a glass-filled polypropylene and
the elastomeric material comprises a thermoplastic-elastomer
comprising ethylene propylene diene rubber and polypropylene.
Particular examples of compatible material sets include, but are
not limited to those listed in Table 1.
TABLE-US-00001 TABLE 1 Suitable elastomeric material and rigid
material combinations. Elastomeric Material Rigid Material
Polypropylene based plastic materials
Acrylonitrile-butadiene-sytrene (ABS) such as SANTOPRENE .RTM. B100
series, based plastic materials grades XB211-55B100 plastic
Polycarbonate based plastic materials material, available from
Advanced ABS/polycarbonate based plastic Elastomer Systems, Akron,
Ohio materials Polystyrene based plastic materials, acrylic based
plastic materials Acrylic-styrene-acrylonitrile (ASA) based plastic
materials Polyethylene terephthalate (PET) based plastic materials
Styrene-ethylene-butylene-styrene Acetal polymer based plastic
materials (SEBS) based plastic materials such as such as CELCON
.RTM. or HOSTAFORM .RTM. THERMOLAST .RTM. K plastic material
plastic material available from available from Kraibur &
Waldkraiburg, Germany Ticona US, Summit, New Jersey Polypropylene
based thermoplastic Anodized aluminum, cold rolled vulcanizate
material which require heat stainless steel, brass, copper, and
other and pressure available from Advanced coated nylon and
polyester fabrics Elastomer Systems, Akron, Ohio Thermoplastic
elastomeric materials ABS based plastic materials, such as ESTAGRIP
.RTM. plastic available polycarbonate based plastic materials from
B.F. Goodrich, Cleveland, Ohio ABS/polycarbonate based plastic
materials, rigid polyvinyl chloride (PVC) based plastic materials
PVC/ABS blend based plastic materials Polyphenylene
oxide/polystyrene blend (PPO/PS) based plastic materials
Thermoplastic elastomeric materials Nylon 6/6 resin, nylon 6 resin
and other such as VERSAFLEX GLS OM600 similar engineering plastic
materials plastic available from GLS Corporation, McHenry, Illinois
materials
[0056] The rigid segments can be fabricated by techniques known in
the art. For example, rigid segments comprised of a polymeric
material can be fabricated by molding the polymeric material.
Features, such as protrusions and indentations, on the rigid
component can be created by casting or molding the polymeric
material in a mold having corresponding features. In some cases,
such features can be created by machining the molded rigid
component. Examples of fabricating techniques include, but not
limited to, extrusion, wherein the polymeric material is forced
through a die that shapes the rigid segment; lamination, wherein
layers or sheets of polymeric material are joined to form a unitary
component; and molding, such as compression, transfer, and/or
injection molding, wherein pressure is applied to promote flow of
the polymeric material in to a cavity.
[0057] Further, the use of adhesives to promote bonding between the
rigid material and the elastomeric material are contemplated by the
present invention. For example, rigid segments can be coated with
adhesive or adhesion promoters known in the art before injecting
the elastomeric material as described in, for example, "Assembly
Bonding of SANTOPRENE.RTM. Thermoplastic Rubber," Advanced
Elastomer Systems Technical Correspondence, TCD00901, 2001.
Alternatively, the selection of particular sets that do not form
thermal bonds is also contemplated by the present invention. Such
embodiments may be advantageously utilized in applications such as
but not limited to articles that require disassembly for
replacement or repair of components. An example of a suitable
non-bonding pair includes SANTOPRENE.RTM. 271-73 thermoplastic
elastomer from Advanced Elastomer Systems, Akron, Ohio and
glass-filled NORYL.RTM.GFN-2 polyphenylene oxide available from GE
Plastics, Pittsfield, Mass.
[0058] Fabrication of components with SANTOPRENE.RTM. thermoplastic
rubber material has been explained in technical literature
including "Processing and Mold Design Considerations for O-Ring
Seals Molded in SANTOPRENE.RTM. Rubber," Advanced Elastomer Systems
Technical Correspondence, TCD07889, 1998; "Design Considerations
for Diaphragms," Advanced Elastomer Systems Technical
Correspondence, TCD00500, 2000; "Assembly Bonding of
SANTOPRENE.RTM. Thermoplastic Rubber," Advanced Elastomer Systems
Technical Correspondence, TCD00901, 2001; "Sealing with
SANTOPRENE.RTM. Thermoplastic Rubber," Advanced Elastomer Systems
Technical Correspondence, TCD02001, 2001; "SANTOPRENE.RTM.
Thermoplastic Rubber for Material Transfer Hose," Advanced
Elastomer Systems Technical Correspondence, TCD1901, 2001;
"Shrinkage Rates for Injection Molding of SANTOPRENE.RTM.
Thermoplastic Rubber, Advanced Elastomer Systems Technical
Correspondence, TCD00601, 2001; "Welding SANTOPRENE.RTM.
Thermoplastic Rubber," Advanced Elastomer Systems Technical
Correspondence, TCD01401, 2001; and "Grip Design Made Easy,"
Advanced Elastomer Systems, AD1095-0201, 2001, each of which are
incorporated herein by reference in their entireties.
[0059] In accordance with one or more embodiments, the present
invention can be used in conjunction with apparatus relevant to
electrically driven separation techniques. For example, the present
invention can be relevant to articles or components utilizing
electrodeionization technology. Electrodeionization apparatus can
be used to remove ionizable species from liquids through the use of
electrically active media under the influence of an electrical
potential to influence the transport of the ionizable species. The
electrically active media may function to alternately collect and
discharge ionizable species, or to facilitate the transport of ions
continuously by ionic or electronic substitution mechanisms.
Electrodeionization apparatus can include media having permanent or
temporary charge and can be operated to cause electrochemical
reactions designed to achieve or enhance performance. These devices
also include electrically active membranes such as semi-permeable
ion exchange membranes, ion-selective is membranes, or bipolar
membranes.
[0060] In accordance with one or more embodiments, the present
invention can be used to fabricate articles or component utilized
in an electrodeionization apparatus. Electrodeionization apparatus
typically include ion-depleting (depleting) compartments and
ion-concentrating (concentrating) compartments. Adjacent
compartments typically have an ion-selective membrane positioned
therebetween. The assembly of concentrating and depleting
compartments, typically known as the stack, may be in alternating
order or in any of various arrangements necessary to satisfy design
and performance requirements. The stack arrangement is typically
bordered by an electrode compartment at one end and another
electrode compartment at an opposite end. Typically, end blocks are
positioned adjacent to electrode compartment, which contain the
electrodes. The concentrating and depleting compartments are
typically defined by spacers or structures that offset and support
ion-selective membranes. The spacer, along with the ion-selective
membrane bonded or sealed thereon, define a cavity which may serve
as a concentrating or a depleting compartment, depending on
operating conditions. A typical electrodeionization apparatus has
alternating electroactive semi-permeable anion- and
cation-selective membranes. The spaces between the ion-selective
membranes are typically configured to create liquid flow
compartments. A transverse DC electrical field is imposed by an
external power source through electrodes at the bounds of the
compartments. Upon imposition of the electric field, ions in the
liquid to be treated in one compartment, the ion-depleting
compartments, are attracted to their respective attracting
electrodes. The ions typically migrate through the ion-selective
membranes into the adjoining compartments so that the liquid in
such adjoining ion-concentrating compartments become ionically
concentrated. The volume within the depleting compartments and, in
some cases, within the concentrating compartments, includes
electrically active media. In electrodeionization apparatus, the
electroactive media-may include intimately mixed or layered anion
and cation exchange resins. Such electroactive media typically
enhances the transport of ions within the compartments and may
participate as a substrate for controlled electrochemical
reactions. As mentioned above, electrodeionization devices have
been described by, for example, Giuffrida et al. in U.S. Pat. Nos.
4,632,745, 4,925,541 and 5,211,823, by Ganzi in U.S. Pat. Nos.
5,259,936 and 5,316,637, by Parsi et al. in U.S. Pat. No.
5,066,375, by Oren et al. in U.S. Pat. No. 5,154,809 and by Kedem
in U.S. Pat. No. 5,240,579, each of which is incorporated herein by
reference in their entireties.
[0061] The concentrating and depleting compartments can be filled
with cation exchange resins, anion exchange resins or a mixture of
both. The cation and anion exchange resins can be arranged as
mixtures or as layers within any of the depleting, concentrating
and electrode compartments so that a number of layers in a variety
of arrangements can be assembled. The use of mixed bed ion exchange
resins in any of the depleting, concentrating and electrode
compartments, the use of inert resin between layers of beds of
anionic and cationic exchange resins, as well as the use of various
types of anionic and cationic exchange resins, such as those
described by DiMascio et al., in U.S. Pat. No. 5,858,191, which is
incorporated herein by reference in its entirety, is contemplated
to be within the scope of the invention.
[0062] In accordance with another embodiment of the present
invention, a depleting compartment spacer, as illustrated in the
exploded view of FIG. 7, shows a rigid core comprised of first
section or segment 355 and second section or segment 360 secured
together with an elastomeric material network 365 that also forms a
seal 370 on at least a portion of the surface of the rigid core. In
some cases, the elastomeric material further encapsulates the rigid
core and forms a sheath 375 on at least a portion of a surface of
the rigid core as a unitary elastomeric material.
[0063] The present invention can be further understood through the
following examples, which are illustrative in nature and do not
limit the scope of the invention.
EXAMPLE 1
Kitchen Article Fabricated by Injection Bonding and Over-Molding
Techniques
[0064] An injection bonded article is illustrated in FIGS. 8A-8D
wherein a kitchen article can be fabricated according to the
following invention. FIG. 8A is an exploded view of a rigid
components of kitchen article 380 shown in FIG. 8C, showing a first
segment 385 comprised of a nylon resin and a second segment 390
comprised of a nylon resin. FIG. 8C illustrates an assembled
kitchen article with a grip section 420 that can be formed on the
rigid core. FIG. 8D is a cross-sectional view across section d-d of
FIG. 8C showing the grip section of the kitchen article. The
complementary mating segments 385 and 390 can be assembled into
kitchen article 380.
[0065] The complementary mating first and segments 385 and 390 can
be fabricated by molding the nylon resin in respective molds (not
shown). The first segment 385 and second segment 390 can have
complementary features, such as protrusion and indentations (not
shown), such that segments 385 and 390 can be complementary mated
to form a rigid article 380. First segment 385 can gave a first
channel 400 wherein molten TPE resin, such as SANTOPRENE.RTM.
191-70A, can be introduced by injection molding techniques. The TPE
resin is selected to bond with the rigid segments 385 and 390.
Rigid segments 385 and 390 are placed into a mold (not shown). The
molten TPE resin, at a temperature of about 260.degree. C. to about
280.degree. C., is injected into the mold and fills and flows
within channel 400. Continued injection of the molten TPE resin
allows it to flow into secondary channels 405 and further over a
portion of an outer surface 410 of mated rigid segments 395 and 390
to form sheathing 415. In this example, injection of the TPE resin
and over-molding thereon over a portion of the outer surface of the
mated rigid segments can be performed to fabricate kitchen article
380 having a grip section 420 formed on a rigid core.
EXAMPLE 2
In-Line Separation Device Fabricated by Injection Bonding and
Over-Molding Techniques
[0066] This example describes an injection bonded article,
illustrated in FIG. 9 showing an in-line separation device 425 in
accordance with the present invention. Separation device 425
comprises a first rigid segment 430 comprised of a polypropylene
plastic resin and a mating, complementary second rigid segment 435
also comprised of a polypropylene plastic resin. Disposed at an
interface defined between mating rigid segments 430 and 435 is a
separation medium 440. Also shown in FIG. 9 is a support grid 445
disposed to provide structural support to separation medium 440
during use of separation device 425. Securing the first and second
rigid segments 430 and 435 as well as the separation medium 440 and
support grid 445 is an elastomeric material comprised of a TPE
resin, such as SANTOPRENE.RTM. 271-73 thermoplastic elastomer
resin.
[0067] To fabricate the separation device 425, the first and second
segments are placed in a mold (not shown). The elastomeric material
is injected into channel 450 defined between rigid segments 430 and
435. The particular TPE material and the particular rigid segment
material are selected to bond, such as by forming a mechanical,
chemical, and/or thermal bond, upon cooling of the assembled
separation device 425. Selection of the material comprising
separation medium 440 can depend of several factors including, but
not limited to, compatibility with the material to be removed or
separated as well as the fluid carrier, gaseous or liquid, flowing
therethrough, temperature stability during fabrication, and cost.
The separation medium 440 can be based on any technique such as
filtration, osmosis, diffusion, adsorption, chelation, chemical
reaction as well as combinations thereof. Examples of suitable
separation medium 440 include, but are not limited to, screens,
porous media such as porous plastic or metal, sintered media such
as sintered plastic or sintered metal, microfiltration membranes,
ultrafiltration membranes, and membranes with grafted and/or
implanted chemical groups to selectively bind to species to be
removed.
[0068] FIG. 10 is a cross-sectional view of a portion of the
separation device 425 illustrated in FIG. 9 showing a connection
portion 455 of the first segment 430, having a seal 460 formed on a
surface 465 of segment 430. The seal 460 comprises the elastomeric
material can be formed by injection molding and over-molding by
allowing the thermoplastic material to flow through channels (not
shown) to the surface of the rigid segment 430. The features of the
seal can be fabricated by having corresponding features of a mold
(not shown) during fabrication of the separation device 425 by
injection molding and over-molding techniques.
[0069] As in Example 1, fabrication techniques of articles based on
SANTOPRENE.RTM. thermoplastic elastomer materials is described in
various technical literature available from Advanced Elastomer
Systems, Akron, Ohio.
EXAMPLE 3
Disposable and Sealed Consumer Products
[0070] In this example, a disposable or sealed consumer product can
be fabricated according to the present invention. Examples of such
consumer products include, but are not limited to disposable
cameras, including underwater, water-sealed cameras, sealed
cellular telephones, as well as sealed rechargeable flashlights.
FIG. 11A is an exploded view of a disposable camera 470 (shown in
FIG. 11B) having a first rigid segment 475 which can comprise ABS
plastic resin and a second rigid segment 480 which can also
comprise ABS plastic resin. The first and second rigid segments
form a complementary mating rigid core that encapsulates internal
component assembly 485. The second rigid segment comprises channel
490 defined thereon.
[0071] To fabricate the consumer product, the assembled first and
second rigid segments with internal components disposed therein are
placed in a mold (not shown). The mold is heated to a temperature
appropriate to promote flow of an elastomeric material when
injected into the mold to fill channel 490. In the perspective view
illustrated in FIG. 11B, a consumer product, such as a disposable
camera, shows that the elastomeric material can also be over-molded
and encapsulate at least a portion of a surface of the rigid
segments 475 and 480 into sheathing 500.
[0072] FIGS. 11C-11D are perspective views of consumer products in
accordance with the present invention. FIG. 11C shows a sealed
electronic device 505 having mated rigid segments 510 and 515
secured together with an elastomeric material network disposed
between rigid segments which can also form a sheathing 520 on at
least a portion of a surface of the mated rigid segments. FIG. 11D
shows a sealed rechargeable flashlight 525 having mated rigid
segments 530 and 535 secured together with an elastomeric material
network disposed between the rigid segments. The elastomeric
material typically also forms a sheathing 540, which can be shaped
to as a grip, on at least a portion of a surface of the rigid
segments. Further, by forming sheathing 540 to cover the rigid
components, the flashlight 525 can be sealed to be water-tight. The
internally disposed elastomeric material network can form internal
seals further ensuring that the internal components are
individually or collectively fluidly isolated.
EXAMPLE 4
Electrodeionization Apparatus Spacer Fabrication, Assembly in an
Electrodeionization Apparatus and Operation of the
Electrodeionization Apparatus
[0073] In this example, an electrodeionization apparatus spacer was
fabricated according to the present invention. An
electrodeionization apparatus was assembled and comprised a spacer
comprised of a rigid core and an elastomeric material network that
also formed seals and partially encapsulated the rigid core. The
assembled electrodeionization apparatus was placed in service and
operated to purify water.
[0074] FIG. 12 is a perspective view showing an electrodeionization
apparatus spacer 550 fabricated in accordance with the present
invention. The spacer 550 comprised a rigid core 555 and an
elastomeric material network 560 within the rigid core. The spacer
550 further had a peripheral seal 570 disposed on a surface 575 of
the rigid core 555, and a resin cavity seal 580 around the
periphery of resin compartments 585 and 590. The resin cavity seal
580 fluidly sealed adjacent ion-selective membranes (not shown)
against the spacer 550. The elastomeric material network 560 also
formed a sheathing 600 that encapsulated at least a portion of the
rim region of the rigid core 555. The spacer 550 also comprised an
external seal 605 disposed around the periphery of an inlet port
610 and an outlet port 615, as well as throughports 620. The
throughports 620 provide fluid communication through the spacer and
between next adjacent compartments of an electrodeionization
apparatus. The elastomeric material network 560, seals 570, 580,
and 605, and sheathing 600 were comprised of a unitary elastomeric
material formed by injection molding SANTOPRENE.RTM. 271-73
thermoplastic elastomer resin into internal channels in the rigid
core and further injecting the thermoplastic elastomer resin so as
to form the external seals 570, 580, and 605 and the sheathing 600.
Also disposed in the rigid core 555 are conduits 625, 630, and 635,
which provided fluid communication between inlet port 610, resin
cavities 585 and 590, and outlet port 615. An internal seal 640
fluidly isolated internal structures in the rigid core including
conduits 625, 630, and 635, as well inlet port 610, resin cavities
585 and 590, outlet port 615, and throughports 620.
[0075] The rigid core was fabricated from two rigid segments, as
shown in FIG. 7. Rigid segments 355 and 360 were fabricated out of
a glass-filled polypropylene compound available from Compounding
Solutions, Lewiston, Me. The rigid segments were assembled together
in complementarily mating arrangement and disposed in a mold cavity
(not shown). SANTOPRENE.RTM. 271-73 thermoplastic elastomer resin,
available from Advanced Elastomer Systems, Akron, Ohio, was
injected into the molded at about 177.degree. C. to about
204.degree. C. (about 350.degree. F. to about 400.degree. F.) to
form the elastomeric material network 365 (designated as 560 in
FIG. 12). The processing temperature depended on the design and
size of the mold and the injection molding machine, and on
processing variables such as shot size, mold temperature, injection
speed and cycle time. Those skilled in the art would recognize that
specific processing conditions would require slight variation
depending of such factors to fabricate similar articles. The
fabricated spacer was removed from the mold assembly and allowed to
cool.
[0076] An electrodeionization apparatus was assembled using the
electrodeionization apparatus spacer shown in FIG. 12 (herein
called the depleting spacer) to define the depleting compartments.
A similar spacer, also fabricated according to the present
invention and herein called the concentrating spacer, was used to
define the concentrating compartments.
[0077] FIG. 6 shows a concentrating compartment spacer in
accordance with the present invention. This concentrating
compartment spacer comprised a rigid core of glass-filled
polypropylene compound available from Compounding Solutions,
Lewiston, Me. and an unitary elastomeric network of SANTOPRENE.RTM.
271-73 thermoplastic elastomer resin, available from Advanced
Elastomer Systems, Akron, Ohio.
[0078] The assembled electrodeionization apparatus 645, shown in
FIG. 13, had eight depleting spacers 650 and nine concentrating
spacers 655, stacked in an alternating fashion, with heterogeneous
ion-selective membranes 660 disposed between the spacers. The stack
of spacers and ion-selective membranes were bounded by electrodes
665 housed in endblocks 670. Threaded rods 675 and nuts 680 were
used to compress the stack and endblock assembly, to compress the
seals and to counter internal hydrostatic pressure during
operation.
[0079] FIG. 14 is a cross-sectional view of a portion of resin
cavity seal and a portion of resin cavity 585 of the depleting
compartment spacer 550. The resin cavity seal 580 had a profile
having a middle protruded region 685 between recessed regions 690.
Seal 580 also had level regions 695 at the periphery of the seal.
The seal profile was created by providing a mold assembly having
corresponding features complementarily defining the protruded
regions and recessed regions. FIG. 14 shows a portion of the seal
disposed in the electrodeionization apparatus before the
electrodionization apparatus assembly was tightened. In particular,
it shows the ion-selective membrane 660 against the protruded
region 685 of the seal and between the rigid core 700 of the
adjacent concentrating compartment. In this embodiment, the
protruded region 685 had a diameter of about 0.060 inch. A curved
portion 705 of the recessed region 690 had a diameter of about
0.030 inch. The separation distance defining between the wall of
the protruded region 685 and the level region 695 was about 0.018
inch. Once the assembly is tightened, the protruded region 685
would compress and deform to conform with the shape of the membrane
660 and the rigid core 700. In particular, the elastomeric material
comprising the seal would deform under compressive loading into the
space defined by the recessed regions 690. The particular ratios
and dimensions of each of the seal sections were selected to
provide a 30% crush capability. The seals were fabricated to
provide:
R.sub.2.gtoreq.1/2R.sub.1,
H.sub.1.about.1/2H.sub.2, and
A.sub.2.gtoreq.A.sub.1,
wherein H.sub.1 is the greatest dimension of protruded region 685
from a datum 710 defined by level region 695, H.sub.2 is the
greatest dimension of recessed region 690 from datum 710, A.sub.1
is the cross-sectional area included in the protruded region 685
and datum 710, A.sub.2 is the cross-sectional open area included in
the recessed region 690 and datum 710, R.sub.1 is the radius of
protruded region 685, and R.sub.2 is the radius of recessed region
690. Likewise, seals 570 and 605 had similar profiles.
[0080] The depleting compartments were filled with layers of cation
and anion exchange resins, DOWEX.TM. MONOSPHERE.TM. 650C cation
resin, available from The Dow Chemical Company, Midland, Mich. and
a mixture of DOWEX.TM. MARATHON.TM. A anion resin, available from
The Dow Chemical Company, Midland, Mich., and AMBERJET.RTM. 4600
anion resin, available from Rohm and Haas Company, Philadelphia,
Pa. The concentrating compartments were filled with a mixture of
cation and anion resins, DOWEX.TM. MONOSPHERE.TM. 650C cation
resin, DOWEX.TM. MARATHON.TM. A anion resin, and AMBERJET.TM. 4600
anion resin.
[0081] Water to be purified entered the depleting compartment
through inlet port 610 and flows through the spacer in a U-shaped
path defined by conduit 625, resin cavity 585, conduit 630, resin
cavity 590, conduit 635 and out of the spacer through outlet port
615.
[0082] The completed electrodeionization apparatus, shown in FIG.
13, was pressurized with water to over 50 psi without any external
leaks, confirming the effectiveness of the peripheral seals 570.
Cross-leakage between the diluting and concentrating compartments
was measured at 5 psi differential confirming that there was no
leakage and that the seals around the throughports 620 in FIG. 12
effectively fluidly isolated the various structures.
[0083] The electrodeionization apparatus was operated under the
following conditions:
TABLE-US-00002 Feed water flow rate: 110 liter/min Feed water
conductivity: 10 .mu.S/cm Feed water CO.sub.2 concentration: 2.5
ppm Feed water temperature: 10.degree. C. Voltage applied: 130 VDC
Current: 0.3 amp Water recovery: 90%
[0084] The water recovery is the fraction of the feed water that
was purified; the flow rate of the purified product was therefore
100 liter/min.
[0085] The product, purified water, conductivity was measured as
0.059 .mu.S/cm, indicating removal of greater than 99.4% of the
dissolved ions in the feed water. The pressure drop through the
electrodeionization apparatus was measured as 10 psi.
EXAMPLE 5
Disposable and Sealed Fuel Cell
[0086] In this example, a disposable and/or sealed fuel cell can be
fabricated according to the present invention. Fuel cells,
including those based on proton exchange membrane (PEM) technology,
can be used, for example, to power portable electrical equipment
and electronic devices such as laptop computers and cell phones.
Fuels cells can be used in a portable applications especially where
the volumetric power density increases and the cost decreases
through advancement in the design, performance and properties of
components such as the membrane, the electrodes, and the flow field
plates. Examples of fuel cell apparatus, including those based on
proton exchange membrane fuel cell (PEMFC) technology, are
available from Plug Power Inc., Latham, N.Y., and Ballard Power
Systems Inc., Burnaby, BC, Canada.
[0087] FIG. 15 is a cross-sectional view of a portion 715 of a
typical PEMFC. The fuel cell typically has planar
membrane-electrode assemblies (MEA) 720 secured between flow field
plates 725. Each MEA 720 typically comprises a construction
comprising an anode 730, a PEM 735 and a cathode 740. Grooves 745
defined in the flow field plates 725 typically serve as conduits to
facilitate transport of reactant gases, typically hydrogen and
oxygen, to the MEA 720 during operation of the fuel cell. The
plates 725, which are typically fabricated from graphite or
graphite composites, can also serve to collect the current
generated at MEA 720.
[0088] One of the challenges of fuel cell construction is a seal
around a perimeter of the MEA 720. The PEM 735 may serve as a
gasket between adjacent plates. FIG. 16 is an enlarged view of a
portion of a sealed PEMFC shown in FIG. 15. FIG. 16 shows MEA 720
disposed between two adjacent plates 725, contacting at interfaces
770. An aperture 765 defined between plates 725 and outside of
interfaces 770 ensures that the plates 725 are not in electrical
contact. The fuel cell typically has multiply stacked alternating
plates 725 and MEA 720.
[0089] In one embodiment of the invention related to the
fabrication of a seal fuel cell stack, the fuel cell stack is
disposed in a mold (not shown) and molten TPE material is injected
into a channel 750 defined, at least partially, by the grooves 755
in plates 725. Upon cooling, the injected TPE material 760 fills
the spaced defined by channel 755 as well as aperture 765 and forms
a seal 780 around MEA 720. The TPE material 760 is typically
selected to be electrically insulating, compatible with the
operating temperature, and chemically compatible with the reactant
gases. For example, the TPE material can be any of those described
above. Adhesion between the TPE material and the plates is
desirable to minimize the clamping force necessary to maintain
compression on the seals.
[0090] This method of sealing the perimeter of a MEA may be
applicable to other designs of PEMFC including, for example, the
fuel cells with non-planar MEA. The method of the present invention
can also be applicable to sealing membranes in other types of
electrochemical devices, such as electrolytic cells and electrical
purification devices based on, for example, electrodialysis and
electrodeionization technology.
[0091] This invention is not limited in its application to the
details of construction and the arrangement of components set forth
herein or illustrated in the drawings. The invention is capable of
other embodiments and of being practiced or of being carried out in
various ways. Also, the phraseology and terminology used herein is
for the purpose of description and should not be regarded as
limiting. The use of "including," "comprising," "having,"
"containing", "involving," and variations thereof herein, is meant
to encompass the items listed thereafter and equivalents thereof as
well as additional items.
[0092] As used herein, the phrase "mechanically bonded" refers to
structural elements that create or have interlocking features
creating interferences that prevent movement of the secured or
bonded elements and the phrase "chemically bonded" refers to an
interlocking or interpenetrating network or assembly of chemical,
typically molecular, species that involves chemical bonds having a
covalent and/or ionic nature. The phrase "thermally bonded" refers
to a fabrication technique useful in fabricating articles comprised
of a plurality of components by contacting molten material to raise
the temperature of another, or the same, material and melting such
meltable material, preferably locally, and cooling the assembly
such that the solidified molten materials become secured, e.g.,
bonded, to each other. The term "binding" broadly refers to
securing a component or segment to another component or segment to
form an assembly. It includes mechanical bonding, chemical bonding
and thermal bonding techniques as well as other techniques that
fasten one or more components or segments together such as but not
limited to the use of welds, adhesives, cements, and other bonding
agents.
[0093] Also as used herein, the term "rigid" describes a material
that is inflexible at ambient temperature and/or at temperatures
during fabrication or assembly of components of articles of the
invention and the term "flexible" describes a material that is
pliant and at least partially yields and deform in response to an
applied force. The term "elastomeric" refers to a material that
responds to an applied tensile or compressive force and generally
readily returns to its original shape upon release of the applied
force. In some embodiments of the present invention, the term
"elastomeric" refers to a material that comprises a thermosetting
polymer, a thermoplastic polymer, or a combination or blend
thereof. Further, the phrase "thermoplastic elastomer" refers to a
class of materials having a rubber component. Such materials
include those commercially available materials typically referred
to as TPE, thermoplastic rubber (TPR), thermoplastic urethane
(TPU), thermoplastic elastomeric olefin (TEO), and thermoplastic
vulcanizate (TPV).
[0094] Also as used herein, the term "conduit" refers to a
passageway that provides communication, typically fluid
communication, between structures. For example, the conduit can
perform as a manifold fluidly connecting a first structure to one
or more structures, providing one or more flowpaths between the
structures.
[0095] Also as used herein, the phrase "ion exchange resin" refers
to electrically active or electroactive media. The phrase "resin
cavity" refers to a structure designed and constructed to contain,
at least partially, electroactive media. Also as used herein, the
phrase "ion-selective membrane" refers to any selectively permeable
membrane such as cation or anion selective permeable membranes and
which are also referred to as selectively permeable membranes, ion
exchange membrane, semi-permeable ion exchange membranes, and
bipolar membranes.
[0096] Having thus described several aspects of at least one
embodiment of this invention, it is to be appreciated that various
alterations, modifications, and improvements will readily occur to
those skilled in the art. For example, the techniques of injection
bonding and over-molding in accordance with the present invention
can be used to fabricate articles such as a garden water spray
nozzle having rigid segments secured with a TPE network which also
forms a sheathing that serves as a handgrip, a valve comprising
mated rigid segments secured together with an elastomeric material
which also forms a gasket or seal at the interconnection to a hose.
Further, other consumer products, such as water-sealed toys, can be
fabricated in accordance with the present invention. Notably, the
present invention can be used to fabricate components of other
apparatus based on the plate and frame design. For example, the
invention can be used to fabricate plates, of a plate-and-frame
heat exchanger, to have an elastomeric network securing rigid
components and a seal encapsulating a portion of the surface of the
plate. Such alterations, modifications, and improvements are
intended to be part of this disclosure, and are intended to be
within the spirit and scope of the invention. Moreover, the
techniques used in accordance with the present invention include
those known in the art. For example, with reference to molding
techniques, those skilled in the art can design and fabricate molds
or mold segments that allows for optimized flow of elastomeric
material during the fabrication process. In particular, one skilled
in the art of mold design can utilize tools such as computers to
simulate and characterize the flow during fabrication. Further,
non-elastomeric materials can be utilized in the articles and
methods of the present invention. For example, a reactive
non-elastomeric material can be utilized to form the network
securing or boding rigid segments and further forming a sheathing
on a surface of the rigid segments. Accordingly, the foregoing
description and drawings are by way of example only.
* * * * *