U.S. patent application number 15/829666 was filed with the patent office on 2019-02-28 for apparatus, system and method of providing a conformable heater system.
This patent application is currently assigned to Jabil Circuit, Inc.. The applicant listed for this patent is Sai Guruva Avuthu, Ronald Harry Darnell, Nabel M. Ghalib, MaryAlice Gill, Ralph Hugeneck, Arnold Reta, Nathaniel Patrick Richards, Jorg Richstein, Samantha Lynn Stevens, Mark Edward Sussman, Girish Satish Wable. Invention is credited to Sai Guruva Avuthu, Ronald Harry Darnell, Nabel M. Ghalib, MaryAlice Gill, Ralph Hugeneck, Arnold Reta, Nathaniel Patrick Richards, Jorg Richstein, Samantha Lynn Stevens, Mark Edward Sussman, Girish Satish Wable.
Application Number | 20190060583 15/829666 |
Document ID | / |
Family ID | 65436473 |
Filed Date | 2019-02-28 |
View All Diagrams
United States Patent
Application |
20190060583 |
Kind Code |
A1 |
Avuthu; Sai Guruva ; et
al. |
February 28, 2019 |
APPARATUS, SYSTEM AND METHOD OF PROVIDING A CONFORMABLE HEATER
SYSTEM
Abstract
The disclosure is and includes at least an apparatus, system and
method for a flexible heater sensor suitable for association with a
fluid bag. The apparatus, system and method may include a
conformable substrate on a ply of the fluid bag opposite a printed
flexible heater; and a matched function ink set, printed onto at
least one substantially planar face of the substrate. The matched
function ink set forms: at least one conductive layer capable of
receiving current flow from at least one power source; and at least
one dielectric layer capable of at least partially insulating and
at least partially limiting conductivity of the at least one
conductive layer; wherein the matched ink set is matched to
preclude detrimental interactions between the printed inks of each
of the at least one conductive and dielectric layers, and to
preclude detrimental interactions with the conformable substrate;
and wherein the at least one conductive layer and the at least one
dielectric layer comprise a sensing circuit that senses at least
the temperature of fluid within the fluid bag.
Inventors: |
Avuthu; Sai Guruva; (St.
Petersburg, FL) ; Ghalib; Nabel M.; (St. Petersburg,
FL) ; Sussman; Mark Edward; (St. Petersburg, FL)
; Reta; Arnold; (St. Petersburg, FL) ; Stevens;
Samantha Lynn; (St. Petersburg, FL) ; Richards;
Nathaniel Patrick; (St. Petersburg, FL) ; Gill;
MaryAlice; (St. Petersburg, FL) ; Wable; Girish
Satish; (St. Petersburg, FL) ; Darnell; Ronald
Harry; (St. Petersburg, FL) ; Hugeneck; Ralph;
(St. Petersburg, FL) ; Richstein; Jorg; (St.
Petersburg, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Avuthu; Sai Guruva
Ghalib; Nabel M.
Sussman; Mark Edward
Reta; Arnold
Stevens; Samantha Lynn
Richards; Nathaniel Patrick
Gill; MaryAlice
Wable; Girish Satish
Darnell; Ronald Harry
Hugeneck; Ralph
Richstein; Jorg |
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg
St. Petersburg |
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL
FL |
US
US
US
US
US
US
US
US
US
US
US |
|
|
Assignee: |
Jabil Circuit, Inc.
St. Petersburg
FL
|
Family ID: |
65436473 |
Appl. No.: |
15/829666 |
Filed: |
December 1, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15683437 |
Aug 22, 2017 |
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15829666 |
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15689611 |
Aug 29, 2017 |
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15683437 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 5/445 20130101;
H05B 2203/002 20130101; G01K 7/021 20130101; G01K 13/00 20130101;
G01F 23/263 20130101; H05B 1/025 20130101; H05B 2203/013 20130101;
H05B 2203/021 20130101; H05B 3/34 20130101; H05B 3/145 20130101;
H05B 2203/036 20130101; A61M 2205/36 20130101; G01F 23/268
20130101; A61J 1/10 20130101 |
International
Class: |
A61M 5/44 20060101
A61M005/44; A61J 1/10 20060101 A61J001/10; H05B 1/02 20060101
H05B001/02; G01K 7/02 20060101 G01K007/02; H05B 3/34 20060101
H05B003/34; H05B 3/14 20060101 H05B003/14; G01F 23/26 20060101
G01F023/26 |
Claims
1. A flexible heater sensor suitable for association with a fluid
bag, comprising: a conformable substrate on a ply of the fluid bag
opposite a printed flexible heater; a matched function ink set,
printed onto at least one substantially planar face of the
substrate to form: at least one conductive layer capable of
receiving current flow from at least one power source; and at least
one dielectric layer capable of at least partially insulating and
at least partially limiting conductivity of the at least one
conductive layer; wherein the matched ink set is matched to
preclude detrimental interactions between the printed inks of each
of the at least one conductive and dielectric layers, and to
preclude detrimental interactions with the conformable substrate;
and wherein the at least one conductive layer and the at least one
dielectric layer comprise a sensing circuit that senses at least
the temperature of fluid within the fluid bag.
2. The flexible heater sensor of claim 1, wherein the substrate
comprises an inorganic substrate
3. The flexible heater sensor of claim 1, wherein the substrate
comprises one selected from the group consisting of PET, PC, TPU,
nylon, glass, fabric, PEN, and ceramic.
4. The flexible heater sensor of claim 1, wherein the detrimental
interactions occur during at least one of deposition and curing of
the printed inks.
5. The flexible heater sensor of claim 1, wherein the printed inks
in the matched ink set include ones selected from the group
consisting of silver, carbon, PEDOT:PSS, and CNT inks.
6. The flexible heater sensor of claim 1, wherein the printed ink
set withstands environmental factors including at least
moisture.
7. The flexible heater sensor of claim 1, further comprising an
encapsulation that at least partially seals at least the
conformable substrate having the matched function ink set thereon
from environmental factors.
8. The flexible heater sensor of claim 7, wherein the encapsulation
comprises a lamination.
9. The flexible heater sensor of claim 1, wherein the sensing
circuit also senses the fluid level of the fluid in the fluid
bag.
10. The flexible heater sensor of 9, wherein the fluid level
sensing comprises a plurality of capacitive strips.
11. The flexible heater sensor of claim 1, wherein the conformable
substrate comprises the ply.
12. The flexible heater sensor of claim 1, wherein the conformable
substrate is adhered to the ply.
13. The flexible heater sensor of claim 1, wherein the sensing
circuit comprises a wireless sender.
14. The flexible heater sensor of claim 13, wherein the wireless
sender comprises at least one of a Bluetooth, WiFi, NFC, cellular
and RF sender.
15. The flexible heater sensor of claim 13, wherein the wireless
sender interacts data from the sensing circuit to a remote mobile
device app.
16. The flexible heater sensor of claim 15, wherein the mobile
device app comprises a plurality of adjustment algorithms for the
data, including for a type of the fluid bag.
17. The flexible heater sensor of claim 1, wherein the power source
comprises a rechargeable battery.
18. The flexible heater sensor of claim 1, wherein the dielectric
layer insulates aspects of the conductive layers from shorting onto
one another due to the conformability of the conformable
substrate.
19. The flexible heater sensor of claim 1, wherein ones of the
dielectric layers comprise reinforcement layers.
20. The flexible heater sensor of claim 1, wherein the fluid bag is
an IV bag.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S.
application Ser. No. 15/683,437, entitled APPARATUS, SYSTEM AND
METHOD OF PROVIDING A FLUID BAG HEATER, filed on Aug. 22, 2017 and
U.S. application Ser. No. 15/689,611, entitled APPARATUS, SYSTEM
AND METHOD OF PROVIDING A CONFORMABLE HEATER IN WEARABLES, filed on
Aug. 29, 2017, the entireties of which are incorporated herein by
reference.
BACKGROUND
Field of the Disclosure
[0002] The disclosure relates generally to printed electronics and,
more particularly, to a conformable heater, such as for use in
wearables.
Description of the Background
[0003] Printed electronics uses printing, or "additive," methods to
create electrical (and other) devices on various substrates.
Printing typically defines patterns on various substrate materials,
such as using screen printing, flexography, gravure, offset
lithography, and inkjet. Electrically functional electronic or
optical inks are deposited on the substrate using one or more of
these printing techniques, thus creating active or passive devices,
such as transistors, capacitors, resistors and inductive coils.
[0004] Printed electronics may use inorganic or organic inks. These
ink materials may be deposited by solution-based, vacuum-based, or
other processes. Ink layers may be applied one atop another.
Printed electronic features may include be or include
semiconductors, metallic conductors, nanoparticles, nanotubes,
etc.
[0005] Rigid substrates, such as glass and silicon, may be used to
print electronics. Poly(ethylene terephthalate)-foil (PET) is a
common substrate, in part due to its low cost and moderately high
temperature stability. Poly(ethylene naphthalate)- (PEN) and
poly(imide)-foil (PI) are alternative substrates. Alternative
substrates include paper and textiles, although high surface
roughness and high absorbency in such substrates may present issues
in printing electronics thereon. In short, it is typical that a
suitable printed electronics substrate preferably has minimal
roughness, suitable wettability, and low absorbency.
[0006] Printed electronics provide a low-cost, high-volume volume
fabrication. The lower cost enables use in many applications but
generally with decreased performance over "conventional
electronics." Further, the fabrication methodologies onto various
substrates allow for use of electronics in heretofore unknown ways,
at least without substantial increased costs. For example, printing
on flexible substrates allows electronics to be placed on curved
surfaces, without the extraordinary expense that the use of
conventional electronics in such a scenario would require.
[0007] Moreover, conventional electronics typically have lower
limits on feature size. In contrast, higher resolution and smaller
structures may be provided using printed electronics, thus
providing variability in circuit density, precision layering, and
functionality not available using conventional electronics.
[0008] Control of thickness, holes, and material compatibility are
essential in printing electronics. In fact, the selection of the
printing method(s) used may be determined by requirements related
to the printed layers, layer characteristics, and the properties of
the printed materials, such as the aforementioned thicknesses,
holes, and material types, as well as by the economic and technical
considerations of a final, printed product.
[0009] Typically, sheet-based inkjet and screen printing are best
for low-volume, high-precision printed electronics. Gravure, offset
and flexographic printing are more common for high-volume
production. Offset and flexographic printing are often used for
both inorganic and organic conductors and dielectrics, while
gravure printing is highly suitable for quality-sensitive layers,
such as within transistors, due to the high layer quality provided
thereby.
[0010] Inkjets are very versatile, but generally offer a lower
throughput and are better suited for low-viscosity, soluble
materials due to possible nozzle clogging. Screen printing is often
used to produce patterned, thick layers from paste-like materials.
Aerosol jet printing atomizes the ink, and uses a gas flow to focus
printed droplets into a tightly collimated beam.
[0011] Evaporation printing combines high precision screen printing
with material vaporization. Materials are deposited through a high
precision stencil that is "registered" to the substrate. Other
methods of printing may be used, such as microcontact printing and
lithography, such as nano-imprint lithography.
[0012] Electronic functionality and printability may
counter-balance one other, mandating optimization to allow for best
results. By way of example, a higher molecular weight in polymers
enhances conductivity, but diminishes solubility. Further,
viscosity, surface tension and solids content must be tightly
selected and controlled in printing. Cross-layer interactions, as
well as post-deposition procedures and layers, also affect the
characteristics of the final product.
[0013] Printed electronics may provide patterns having features
ranging from 3-10 .mu.m or less in width, and layer thicknesses
from tens of nanometers to more than 10 .mu.m or more. Once
printing and patterning is complete, post treatment of the
substrate may be needed to attain final electrical and mechanical
properties. Post-treatment may be driven more by the specific ink
and substrate combination.
[0014] Typical heaters for use in wearables, such as in garments or
accessories, are manufactured using conventional electronics
techniques and manual labor. For example, rigid, thick, and bulky
heaters are typically provided, such as in association with printed
circuit boards and the like. The wiring that allows for operation
of these thick, bulky heaters is typically sewn into the wearables,
such as between fabric layers, to enclose the heating elements into
the fabrics.
[0015] Moreover, less bulky heaters that are fabricated using
atypical types of processing are typically expensive, in part
because of the complex fabrication steps needed to create such
heaters. Hence, these heaters are not applicable for wearable
applications. Further, either of the foregoing atypical or
conventional types of heaters necessitates an extraordinary level
of encapsulation if the wearable associated with the heater is, for
example, to be laundered. This is particularly the case if the
wearable is to be laundered many times over its life cycle. That
is, the limiting factor in the life cycle of the wearable should
not be the heater provided in association with the wearable.
[0016] Additionally and in an exemplary circumstance, medical bags,
such as medical fluid or blood bags, often require heating.
Typically in the known art, such heating is provided by an
electronic heating hardware unit into which the medical bag must be
placed. Accordingly, relatively large and/or substantially immobile
equipment constitutes the manner in which heat is provided to
medical fluid bags in known embodiments.
[0017] Less bulky heaters that are fabricated using atypical types
of processing may provide enhanced mobility, but are typically very
expensive, in part because of the complex fabrication steps needed
to create such heaters, and are generally not highly reliable.
Hence, these heaters are not presently applicable for use in
heating in wearables or medical bags.
[0018] Therefore, less bulky heaters that may be assembled using
in-line and/or high throughput processes, such as additive printing
processes, and which is thus less complex in its fabrication
resulting in more cost-efficient manufacturing, longer use life of
the heater and the wearable, and other distinct advantages, is
needed. Such a heater should be formed in a thin, less bulky, more
conformable and flexible format, and on a moldable substrate, to
not only address the foregoing concerns, but also to allow for
integration into more diverse types of uses.
[0019] Further, presently the characteristics, such as temperature,
of a fluid bag, such as a medical fluid bag, are typically
monitored using off bag components, such as including a
thermocouple to the bag or an infrared gun, by way of nonlimiting
example. Such methods, however, may frequently subject the bag to
improper temperature measurements because of, for example, human
error, environmental or electrical interference between the bag and
the temperature reader, component failure due to the need for
various additional normal components to make the electrical
connection from the bag to the reader, and so on.
[0020] Additionally, present methods of indicating the level of
fluid in a bag, such as a medical fluid bag, are limited to weight
measurements, such as wherein a bag placed on an IV stand pulls
down on a hook that is electrically associated with a measurement
scale. Such methods of measuring a level of fluid remaining in the
bag are highly inaccurate, however, at least because of the
possibility of human error, such as someone pulling down on the
bag, environmental and/or use factors, such as shaking of the scale
hook when the IV stand is moved, the breaking of electrical
connections when an IV stand is moved, and so on.
[0021] Yet further, in part due to the inaccuracy of temperature
and level sensing presently available in conjunction with fluid
bags, methods of conveying temperature and fluid level data to one
or more interested parties are presently wholly inadequate. For
example, the reading on an infrared gun may be inaccurate for the
reasons stated above, such as human error wherein equipment or body
parts come between the IR gun and the bag. Further, the readout of
a scale and attempt to sense fluid level in a bag may require
conversion by a human user, or may be inaccurate for all of the
foregoing reasons and additionally because of lack of accounting
for the weight of the bag itself, by way of example.
[0022] Therefore, the need exists not only for improved designs and
printing methods to place a heater in association with a fluid bag,
such as a medical fluid bag, but additionally for improved
methodologies of associating bag characteristic measurements, such
as temperature measurement and level sensing, with a fluid bag, and
additionally of providing the data logged in association with such
temperature sensing and level sensing to one or more interested
users.
SUMMARY
[0023] Thus, the disclosure provides at least an apparatus, system
and method for a flexible heater. The flexible heater comprises a
conformable substrate; a matched function ink set, printed onto at
least one substantially planar face of the substrate to form at
least a conductive layer capable of receiving current flow from at
least one power source; a resistive layer electrically associated
with the at least one conductive layer and comprising a plurality
of heating elements capable of generating heat upon receipt of the
current flow; and a dielectric layer capable of at least partially
insulating the at least one resistive layer, wherein the matched
ink set is matched to preclude detrimental interactions between the
printed inks of each of the at least one conductive, resistive and
dielectric layers, and to preclude detrimental interactions with
the conformable substrate.
[0024] The flexible heater may additionally include an
encapsulation that at least partially seals at least the
conformable substrate having the matched function ink set thereon
from environmental factors. The flexible heater may additionally be
integrated into the wearable of the conformable substrate having
the matched ink set thereon.
[0025] The flexible heater may further comprise a driver circuit
connectively associated with the at least one conductive layer. The
driver circuit may comprise a control system, and wherein an amount
of heat delivered by the heating elements is controlled by the
control system.
[0026] The disclosure also is and includes at least an apparatus,
system and method for a flexible heater sensor suitable for
association with a fluid bag. The apparatus, system and method may
include a conformable substrate on a ply of the fluid bag opposite
a printed flexible heater; and a matched function ink set, printed
onto at least one substantially planar face of the substrate. The
matched function ink set forms: at least one conductive layer
capable of receiving current flow from at least one power source;
and at least one dielectric layer capable of at least partially
insulating and at least partially limiting conductivity of the at
least one conductive layer; wherein the matched ink set is matched
to preclude detrimental interactions between the printed inks of
each of the at least one conductive and dielectric layers, and to
preclude detrimental interactions with the conformable substrate;
and wherein the at least one conductive layer and the at least one
dielectric layer comprise a sensing circuit that senses at least
the temperature of fluid within the fluid bag.
[0027] Thus, the disclosure provides improved designs and printing
methods to place a heater in association with a fluid bag, such as
a medical fluid bag, wearables, and additionally for improved
methodologies of associating bag characteristic measurements, such
as temperature measurement and level sensing, with a fluid bag, and
additionally of providing the data logged in association with such
temperature sensing and level sensing to one or more interested
users.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The exemplary compositions, systems, and methods shall be
described hereinafter with reference to the attached drawings,
which are given as non-limiting examples only, in which:
[0029] FIG. 1 is a schematic and block diagram illustrating a
heater according to the embodiments;
[0030] FIG. 2 is a schematic and block diagram illustrating a
heater according to the embodiments;
[0031] FIG. 3 is an exemplary implementation of the embodiments
having a conductor layer with contact points at the top right and
bottom left of the heating system;
[0032] FIG. 4 is an exemplary implementation of a conductive and
resistive layer heating system;
[0033] FIG. 5 is an exemplary implementation of an embodiment
having an enhanced size of the conductive layer associated with the
contact pads at the top of the device;
[0034] FIG. 6 illustrates an exemplary implementation of a heating
system enclosed in an encapsulation layer;
[0035] FIG. 7 illustrates an exemplary implementation in which the
heating system is laminated to a textile;
[0036] FIG. 8 is a flow diagram illustrating an exemplary method of
providing a conformable heater, such as for use in a wearable;
[0037] FIG. 9 is a flow diagram illustrating a method of using a
conformable heater system within a wearable;
[0038] FIG. 10 is an illustration of an exemplary sensing
circuit;
[0039] FIGS. 11A-11D are illustrations of exemplary heating
circuits;
[0040] FIG. 12 is an illustration of an exemplary sensing
circuit;
[0041] FIGS. 13A-13B are illustrations of exemplary sensing
circuits;
[0042] FIGS. 14A-14C are illustrations of exemplary mobile apps for
sensor data;
[0043] FIG. 15 is an illustration of an exemplary sensing
circuit;
[0044] FIG. 16 is an illustration of an exemplary sensing circuit;
and
[0045] FIGS. 17A-17C are illustrations of exemplary sensing
circuits.
DETAILED DESCRIPTION
[0046] The figures and descriptions provided herein may have been
simplified to illustrate aspects that are relevant for a clear
understanding of the herein described apparatuses, systems, and
methods, while eliminating, for the purpose of clarity, other
aspects that may be found in typical similar devices, systems, and
methods. Those of ordinary skill may thus recognize that other
elements and/or operations may be desirable and/or necessary to
implement the devices, systems, and methods described herein. But
because such elements and operations are known in the art, and
because they do not facilitate a better understanding of the
present disclosure, for the sake of brevity a discussion of such
elements and operations may not be provided herein. However, the
present disclosure is deemed to nevertheless include all such
elements, variations, and modifications to the described aspects
that would be known to those of ordinary skill in the art.
[0047] Embodiments are provided throughout so that this disclosure
is sufficiently thorough and fully conveys the scope of the
disclosed embodiments to those who are skilled in the art. Numerous
specific details are set forth, such as examples of specific
components, devices, and methods, to provide a thorough
understanding of embodiments of the present disclosure.
Nevertheless, it will be apparent to those skilled in the art that
certain specific disclosed details need not be employed, and that
embodiments may be embodied in different forms. As such, the
embodiments should not be construed to limit the scope of the
disclosure. As referenced above, in some embodiments, well-known
processes, well-known device structures, and well-known
technologies may not be described in detail.
[0048] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting. For
example, as used herein, the singular forms "a", "an" and "the" may
be intended to include the plural forms as well, unless the context
clearly indicates otherwise. The terms "comprises," "comprising,"
"including," and "having," are inclusive and therefore specify the
presence of stated features, integers, steps, operations, elements,
and/or components, but do not preclude the presence or addition of
one or more other features, integers, steps, operations, elements,
components, and/or groups thereof. The steps, processes, and
operations described herein are not to be construed as necessarily
requiring their respective performance in the particular order
discussed or illustrated, unless specifically identified as a
preferred or required order of performance. It is also to be
understood that additional or alternative steps may be employed, in
place of or in conjunction with the disclosed aspects.
[0049] When an element or layer is referred to as being "on",
"upon", "connected to" or "coupled to" another element or layer, it
may be directly on, upon, connected or coupled to the other element
or layer, or intervening elements or layers may be present, unless
clearly indicated otherwise. In contrast, when an element or layer
is referred to as being "directly on," "directly upon", "directly
connected to" or "directly coupled to" another element or layer,
there may be no intervening elements or layers present. Other words
used to describe the relationship between elements should be
interpreted in a like fashion (e.g., "between" versus "directly
between," "adjacent" versus "directly adjacent," etc.). Further, as
used herein the term "and/or" includes any and all combinations of
one or more of the associated listed items.
[0050] Yet further, although the terms first, second, third, etc.
may be used herein to describe various elements, components,
regions, layers and/or sections, these elements, components,
regions, layers and/or sections should not be limited by these
terms. These terms may be only used to distinguish one element,
component, region, layer or section from another element,
component, region, layer or section. Terms such as "first,"
"second," and other numerical terms when used herein do not imply a
sequence or order unless clearly indicated by the context. Thus, a
first element, component, region, layer or section discussed below
could be termed a second element, component, region, layer or
section without departing from the teachings of the
embodiments.
[0051] Historically and as discussed throughout, the formation of
many small aspects of devices or small devices has generally
integrated the processes of deposition and etching. That is,
traces, such as conductive traces, dielectric traces, insulating
traces, and the like, which include formation of device features
such as wave guides, vias, connectors, and the like, have generally
been formed by subtractive processes, i.e., by creating layers
which were later etched to remove portions of those layers to form
the desired topologies and features of a device.
[0052] Additive printing processes have been developed whereby
device features and aspects are additively formed, i.e., are formed
by "printing" the desired feature at the desired location and in
the desired shape. This has allowed for many devices and elements
of devices that were previously formed using subtractive processes
to be formed via additive processes, including, but not limited to,
printed transistors, carbon-resistive heating elements,
piezo-elements and audio elements, photodetectors and emitters, and
devices for medical use, such as glucose strips and ECG straps.
[0053] In short, the printing of such devices is dependent on a
number of factors, including matching deposited materials, such as
inks, to substrates for particular applications. This ability to
use a variety of substrates may afford unique properties to printed
devices that was previously unknown in etched devices, such as the
ability for devices to stretch and bend, and to be used in
previously unknown or inhospitable environments, such as use as
conformable heaters in wearables that are to be laundered. By way
of non-limiting example, the ability to print electronic traces on
plasticized substrates allows for those substrates to be conformed
after printing has occurred.
[0054] However, known additive properties do present limitations
over the properties previously available using subtractive
processing. For example, it is typical that conductive traces
formed using additive processes have more limited conductivity than
the conductive traces previously formed using subtractive
processes. This is, in part, because pure copper traces provided
using subtractive processes are presently unavailable to be printed
using modern additive processing. Accordingly, some devices and
elements thereof, such as heaters, may be subjected to substantial
modification in order to accommodate the modified properties
available using printed traces in additive processes, as compared
to the use of conventional electronics-formation techniques.
[0055] In the embodiments, a large number of factors must be
balanced in each unique application in order to best arrive at
properties that most closely approximate those properties
previously available only in subtractive processes. For example, in
the disclosed devices and processes for creating those devices,
compatibility must be assessed as between a substrate for printing
and the receptivity of such substrate, the inks employed and the
conductivity thereof, the fineness of the printed traces used, the
pitch, density and consistency of the printed inks, the type of
printing performed, i.e., screen printing versus other types of
printing, the thickness of the printed layers, and the like.
Moreover, because multiple inks may be employed in order to create
the disclosed heating elements, the compatibility of the inks used
with one another is also an aspect of the embodiments. For example,
chemical reactions between inks, different curing methodologies
between inks, and the manner of deposition as between inks must all
be assessed for all inks within a given ink set. Also of note, the
skilled artisan will appreciate, in light of the discussion herein,
that different inks within an ink set may have variable
characteristics even after deposition. For example, certain inks
may suffer from a valley effect in the center of a deposited trace
of that ink, while peaks are created at the outer part of traces
using that ink. Accordingly, because the thickness of a trace
deposited using such an ink may allow for alleviation or
heightening of the foregoing effect, the manner and consistency of
application of each ink within an ink set is noteworthy in the
embodiments.
[0056] In the known art of incorporated heaters, printed circuit
boards needed to be mechanically integrated, and hence accounted
for, within each product. However, the ability to use printed
electronics with flexible substrates and substrates having uneven
topologies may allow for printed electronics to be integrated as
part of a product, instead of necessitating a mechanical
integration of the electronics into the finished product. Needless
to say, this may include the use of printed electronics onto
substrates unsuitable for accepting electronics created using
subtractive processes, such as fabrics, plastics that do not
provide "sticky" surfaces, organic substrates, and the like. This
may occur, for example, because additive processes allow for
different printing types within each subsequently printed layer of
the printed device, and thereby the functionality provided by each
layer, such as mechanical, electrical, structural, or other
functionality, may be varied as between printed layers throughout a
deposition process.
[0057] Various solutions to balance the foregoing factors may be
provided using additive processing. For example, a flexible
substrate may be provided, wherein printing occurs on one or both
sides of the substrate, such as on one or both sides of a medical
bag. Thereby, traces may be produced on one or both sides of the
bag to form one heater unit, or series or parallel heaters. In such
instances, one or more vias may be created between the sides of the
bag, thus producing one heating system, or multiple heat systems on
opposing sides of the bag may be connectible through or around the
contents of the bag.
[0058] The embodiments provide at least a printed heater on a fluid
bag substrate, such as a medical grade substrate as may be used for
IV fluids, blood bags, or the like, or on a flexible substrate for
use in association with a wearable, that is formed of a layer or
layers of functional ink(s), such as conductive inks, resistive
inks, and insulating inks, formed into traces using additive
processes to thereby effectuate the heater unit. Additional printed
electronics may also be provided using the same or similar additive
processes, such as electronics including sensors, antennas, such as
RF, NFC, or the like antennas, thermometers, thermocouples, fluid
sensors, and the like.
[0059] The embodiments may accordingly provide not only heaters for
heating, such as of wearable or of fluid within a bag, but
additionally sensors integrated with the bag, such as to allow for
traceability, network connectivity, and patient care reporting.
This traceability, connectivity, and reporting may be manual or
automatic, and may be occasional, periodic, semi-continuous, and/or
continuous in accordance with the embodiments. These
functionalities may allow for reductions in human error in patient
monitoring and reporting, for example.
[0060] In accordance with the foregoing, the embodiments provide
less bulky heating equipment, such as to allow for optimized
conditions in cramped spaces, such as in clothing, or in operating
rooms or ambulances. Further, the embodiments provide improved
patient care by regulating the heating of medical fluids to ensure
the fluids do not under- or overheat and cause patient discomfort,
injury, or death. Further, such heaters may provide improved user
comfort and ease of use.
[0061] Medical bags provide unique impediments to allowing for the
use of additive processes, such as the printing of electronics, in
association therewith. For example, because a medical bag typically
has a texture associated therewith, and is highly resistant to
tearing and puncture, and hence is thick and highly flexible in
association with the texturing, a medical bag provides a unique
substrate for additive processes. Further, a medical bag must be
inert in its properties in order to allow for maintenance of
sanitary conditions in association with patient care. The disclosed
embodiments may be used in association with any such fluid bag, or
with any other bag or substrate having such impediments to printing
thereon, such as a flexible substrate for inclusion in a wearable.
Furthermore, the disclosed embodiments may be used with any
substrate of any size or shape.
[0062] More particularly, in the embodiments, a flexible heater for
use in a wearable or on a fluid bag may be printed onto a flexible
and conformable organic or inorganic substrate, such as using a
"matched function" ink set. The flexible heater may be comprised of
multiple layers of inks or substances forming the matched function
set. For example, and as illustrated with respect to the heater 10
of FIG. 1, a conductive layer 12 may be printed onto substrate 14
to allow for current flow 16 to the heater. A resistive layer 18
may also or subsequently be printed to allow for the heating effect
20 to occur upon heating of the resistors due to the current flow
16 therethrough. Further, a dielectric layer 22 may be printed to
insulate the resistive elements 18a, both from shorting onto one
another because of the conformable, flexible nature of the
substrate 14, and to insulate the heat produced by the heating
elements 18a to avoid localized overheating.
[0063] Of course, the third layer 22 may additionally be provided
below or between other layers 12, 18. For example, in a particular
exemplary embodiment, a printed heater not including a dielectric
layer 106 may be limited in operation to a temperature range of 45
to 50 degrees Celsius; but the same heater including a dielectric
layer 22 may be operated in a temperature range of 45 to 65 degrees
Celsius without concern that the excessive heat will pass
improperly from the heater out into contact with the environment,
such as a hand placed on or near a fluid bag 50.
[0064] The substrate 14 onto which the layers 12, 18, 22 are
printed may include both organic and inorganic substrates, subject
to the limitation that substrates may be flexible and/or
conformable to the wearable or fluid bag into or onto which the
heater 10 is placed. Suitable substrates may include, but are not
limited to PET, PC, TPU, nylon, glass, fabric, PEN, and
ceramics.
[0065] As referenced above, various inks and ink sets may be used
to form the layers 12, 18, 22, or aspects thereof, in heater 10,
and inks within the set may be matched to one another so as to
avoid undesired chemical interactions during deposition, curing,
etc., and/or may be matched to the substrate onto which the inks
are to be printed. By way of non-limiting example, conductive and
resistive inks used may include silver, carbon, PEDOT:PSS, CNT, or
a variety of other printable, conductive, dielectric and/or
resistive materials that will be apparent to the skilled artisan in
light of the discussion herein.
[0066] In certain embodiments, particularly those exposed to the
elements and/or intended for laundering, or for use in harsh or
sterile operating room conditions, the heating system 10 may
preferably be encapsulated in order to increase durability. In such
cases, isolation from environmental conditions 30, such as wet
conditions, including rain, snow, or humidity, and/or insulation
from wash and dry cycles and/or general robust handling, may be
performed. In such cases, an encapsulation system 32, such as a
laminated pouch, may be optionally provided to enclose the heating
system 10, and, in such cases, the encapsulation 32 may include
connectivity and/or pass-throughs to allow for the provision of
power 40 through the encapsulation system 32 to the heating system
10. Finally, the heating system 10, such as including the
encapsulation 32, may be integrated into a wearable or bag 50 via
any known method, such as by sewing, lamination, or the like.
[0067] Thus, encapsulation 32 may provide waterproofing,
airproofing, or the like in order to protect the heating system and
associated systems from any adverse environmental factors 30. To
provide the encapsulation 32, various known techniques may be
employed. For example, acrylics may be laminated onto each side of
the heater substrate 14, such as to create a sealed lamination lip
around the substrate 14, with the only projections extending
therefrom having the acrylic lamination seal therearound. Further,
such a laminated pouch may be treated with, for example,
ultra-violet radiation such that the lamination is sealed onto, and
provides maximum protection of, the heating system 10. Of note
however, the more layers that are added to the heating system, such
as including encapsulation 32, the less conformable to the wearable
the heating system will become, particularly in the case where
added layers have significant thickness thereto.
[0068] In some embodiments, the encapsulation 32 that protects from
environmental conditions 30 may not require any secondary effort
beyond production of the heating system 10. For example, substrate
and ink combinations may be selected that are submersible and
conformable, or only that portion of the substrate having printed
electronics thereon to provide the heating system may be sealed,
such as with a single acrylic laminate, from environmental
conditions.
[0069] As referenced above, heating systems 10 with or without
encapsulation 32 connect to one or more driving circuits 52. In
certain embodiments, interconnection 54 to, for example, driver
circuit 52 and/or power 40, may include a high contact surface
area, such as to enable the heating system 10 to draw significant
current 16 from the power source 40. Also as referenced above,
interconnection 54 may also include or comprise printed electronic
surfaces. Such interconnections 54 may additionally include
classical wiring, micro-connection, and/or electromechanical
connection techniques, by way of non-limiting example.
[0070] The various interconnections 54, such including those from
the driver circuit 52 to external control systems, if any, and/or
to the power supply 56, may extend outwardly from the heating
system 10. These interconnections 54, as well as data requirements
and power requirements, may be dependent on the unique structure of
a given heating system 10. For example, different carbon inks
applied in the formulation of the heating system 10 may have
different power requirements, such as 5-15 volts, or more
particularly 5, 9, or 12 volts, by way of non-limiting example.
[0071] Similarly, interconnects 54 may also be or include one or
more universal connectors known in the art for connectivity to, for
example, the aforementioned voltages. Further, such a universal
connector may be or include other known connector types, such as
USB, micro-USB, mini-USB, lightning connector, and other known
interconnects. Additionally and alternatively, proprietary
interconnects 54 may be provided in conjunction with the
embodiments.
[0072] The aforementioned driving circuit 52 may or may not be in
direct physical association with the heating system 10 and the
interconnects 54. By way of example, the driver circuit 52 may be
included as a self-contained system in the electrical pathway
between the power source 40 and the heating system 10. The driver
circuit 52 may include control systems 52a or connectivity to
control systems 52b, such as to allow for remote and/or wireless
control of the heating system 10, and/or to provide limitations on
the heating system, such as amount of heat delivered, amount of
current delivered or power drawn, variation between different heat
delivery levels, and the like. Such remote connectivity may include
wireless connectivity, such as using NFC, blue tooth, WiFi, or
cellular connectivity, such as to link to an app 60 on a user's
mobile device 62, by way of non-limiting example.
[0073] Of note, the control system(s) 52a, b, such as a
Bluetooth-based control system, may allow for a change in
temperature automatically or manually, as referenced herein.
Accordingly, the control system(s) 52a, b may communicate, such as
via Bluetooth, radio-frequency (RF), near-field communications
(NFC), or the like, with a secondary controlling device, such as an
app on a mobile device or an app or application on a medical
monitoring system.
[0074] The aforementioned change may occur only for a certain
period of time, which may be brief, such as particularly if the
control system indicates that significant power will be consumed on
a desired setting. For example, it may be manually or automatically
selected that a user has pre-set a heater to heat to 85 degrees for
90 seconds, such as only while the user briefly walks a dog outside
in 10 degree weather, because it is understood that the user can
recharge the system completely immediately after the short-term
use. However, if a user is going on a one hour jog, and that jog is
in the same 10 degree weather, the user may prefer that the heater
operate at 45 degrees for 50 minutes of the hour before the charge
is fully consumed.
[0075] The power source 40 that delivers power to the heating
system 10, such as through the driver circuit 52, may be
battery-driven, as mentioned above, if local utility power is not
available. The power source in such instances may preferably
provide a battery life of, for example, 2-10 hours, or, more
specifically, 4-8 hours. This power may be provided, for example,
from a permanent power delivery system embedded in a garment or on
a bag or IV-fluid pole, such as may use a rechargeable, removable,
replaceable, or permanent battery, by way of non-limiting example,
or by a secondary power source suitable to be plugged into the
driver circuit system, such as may be embedded in or associated
with utility-provided power, medical equipment, a mobile device or
other mobile power source, via a proprietary or non-proprietary
connector, such as via a micro USB, lightning connector, or the
like. As referenced, typical power provision elements may include
batteries, such as rechargeable batteries, such as lithium ion
batteries. Such batteries may typically provide high levels of
heating very quickly, and then allow for a quick ramp-down in heat
delivery to avoid unnecessary power use during the ramp-up or
ramp-down phases of power provision.
[0076] Atypical power sources may additionally be used to provide
the power source 40 for heating system 10. For example, kinetic
power sources, such as those that store power based on movement,
and/or other similar magnetic and/or piezo-electric power systems,
may be embedded in or connectable to the wearable in order to
provide primary, secondary, permanent, or temporary power to the
heating system 10 via the driver circuit 52. Likewise, primary,
secondary, and/or atypical power source(s) 40 may work together and
in conjunction with the aforementioned system control, such as may
be embedded in or communicatively associated with the driver
circuit 52, to deliver power only upon particular triggers. For
example, a wearable equipped with heaters at multiple locations,
such as in the elbow of a sweatshirt and in the upper back region,
may allow individual ones of those locations to be activated only
upon certain events indicated by on-board, such as printed
electronic, sensors 70, which may additionally be associated with
the substrate 12. For example, a kinetic sensor may sense movement,
and during the movement phase may activate a heater in a given
location, such as in the upper back region in the prior example.
However, upon sensing by the kinetic sensor of the stoppage of
movement, the heating element in the elbow of the sweatshirt may be
activated. This may be done for any of a variety of reasons
understood to the skilled artisan, such as for a pitcher who stops
pitching between innings, but wishes to keep his or her elbow
"warm" so as to avoid injury.
[0077] Such variations in heating elements may not only occur for
wearables having multiple heaters, but may similarly include
variable heater designs for different purposes. For example,
smaller heaters consume appreciably less power than larger heaters,
and thus necessitate a lower level power supply. Consequently, in
the prior example of a sweatshirt for a pitcher, a small heater
located only proximate to the pitcher's "Tommy John" ligament in
his or her elbow may require little power for activation, but may
nevertheless be enabled to deliver significant health impact to the
wearer, such as to keep this oft-injured ligament warm after
inactivity of more than 10 minutes has occurred.
[0078] Moreover, variability in heat levels, such as may be
indicated by the driver circuit system, may be made manually by the
user or automatically based on system characteristics. For example,
lower levels of heat in a hand warmer heating system, such as may
be embedded in the pockets of a sweatshirt or in a user's gloves,
may be needed if the temperature is colder, i.e., only a particular
temperature differential from environmental conditions may be
necessary in order to make a user feel "warm". That is, a user in
an environment where the temperature is 10 degrees Fahrenheit may
feel much warmer if the user's gloves are warmed to 40 degrees
Fahrenheit, rather than warming the gloves all the way to a maximum
heating level of 65 degrees. However, in the event the ambient
temperature is 35 degrees, the user may need the heating element to
go to 65 degrees in order for the user to feel the same level of
"warmth".
[0079] Additional considerations in power delivered to the heater
and/or in the heat delivered may occur based on the use case of the
wearable and of the heater. For example, in instances in which the
heater might be in substantially direct contact with or very close
to the user's skin, the control system associated with the driver
circuit 52 discussed herein must limit the power such that the
heating is not sufficient to burn, cause discomfort to, or
otherwise harm the user. Such concerns may be addressed, in part,
through the use of self-regulating inks to provide the heating
elements in certain exemplary embodiments.
[0080] For example, a positive temperature coefficient (PTC) heater
may provide a self-regulating heater. A self-regulating heater
stabilizes at a specific temperature as current runs through the
heater. That is, as temperature is increased the resistance of the
self-regulating heater also increases, which causes reduced current
flow and, accordingly, an inability of the heater to continue
increasing in temperature. On the contrary, if the temperature is
reduced, the resistance decreases, thereby allowing more current to
pass through the device. In a typical embodiment, a
self-regulating/PTC heater thus provides a stabilized temperature
that is independent of the voltage applied to the heater.
[0081] Secondary systems 202 may be provided in conjunction with
heating system 10, such as to hold in warmth, as illustrated in
FIG. 2. For example, in an embodiment having a laterally crossing
pocket 204 in a sweatshirt, the single pocket across the sweatshirt
may be lined 202 on the interior portion thereof, and may have the
heating element provided interior to the lining of the pocket
thereof, in order that the heat generated from the heating system
10 is held within the pocket 204 of the sweatshirt to the maximum
extent possible.
[0082] As discussed throughout, it may be advantageous,
particularly for certain types of wearables or fluid bags, that the
heating system and/or the other systems associated therewith be
conformable. This conformability may apply to the application of
forces by the user or based on the activity, conformance to the
physical profile of the wearable/bag itself, or the like.
Additional considerations may arise due to the conformability of
the heating system and/or its associated systems. For example,
delivered heat levels may vary based on the physical configuration
of the heating elements, i.e., when the heating system is bent or
partially folded, it may deliver greater or lesser heat in certain
spots than is anticipated. Needless to say, some of this
variability may be accounted for using a protective dielectric
layer 22, such as is referenced above.
[0083] As discussed throughout, additional sensors, integrated
circuits, memory, and the like may also be associated with the
discussed heating system 10, may be printed on the substrate 14
thereof, and/or may be formed on or in systems associated
therewith, and/or on the substrates thereof. It goes without saying
that, in such embodiments, the associated electronics may be
discrete from the heating system and those systems associated with
the heating system, but may nevertheless be similarly conformable
to the wearable, the substrate of the heating system, and so on.
Further, those skilled in the art will appreciate that such other
electronic circuits may or may not be formed by printing processes
on the same substrate, or on a physically adjacent substrate, of
the heating system.
[0084] Moreover, the embodiments may include additional layers (not
shown) to those discussed above. For example, a heater substrate
may be provided in the form of a highly adhesive sticker, wherein
the sticker may or may not provide a substrate suitable for
receiving printed electronics on one side of the "sticker." In such
an instance, the compatibly adhesive surface may be applied to the
opposing face of the sticker, such as via additive process
printing, lamination, deposition, or the like.
[0085] Of note, in order to associate the printed electronic layers
with a substrate throughout this disclosure, ink sets may be
selected in light of process parameters to form the heater and the
operation environment in which the bag will be used. For example,
not only is application and curing of each ink important in light
of the function to be imparted to the bag, but additionally the
effects of operating conditions on each ink must be considered. In
short, material compatibility must be maintained, and a chemical
inertness must be present between the additive process elements. By
way of nonlimiting example, the ink solvents used in relation to
the inkset may be necessarily inert with respect to both an IV bag,
and the sanitary nature and operating environment of the bag.
Further, sterilization of the bag using radioactive or ultraviolet
processes, if needed, should not degrade the printed electronic
materials in the inkset or the functionality provided thereby. Yet
further, the surface energy of the substrate must be matched to the
applied inks, layers, and/or coatings of the inkset and onto the
substrate. Additionally, the curing temperatures of any inks or
layers in the inkset must be considered in light of the melting or
degradation temperature of the bag itself. For example, bags formed
of certain polymers cannot be subjected to heat levels sufficient
to cure certain types of frequently used printed electronic
inks.
[0086] In order to address certain of the foregoing of the concerns
and yet obtain sufficient curing of the ink and additive process
layers, different types of curing methodologies may be used in the
embodiments. For example, convection curing using a convection box
or conveyor belt may be used to apply sufficient curing energy;
likewise, infrared or near infrared energy may be applied;
additionally, ultraviolet curing may be used; and photonic curing
may also be employed. Yet further, ramping temperatures may be used
in order to provide sufficient levels of curing, such as wherein
high or low temperatures are employed to improve the ability of the
print substrate to withstand more heat or energy than might
otherwise be the case.
[0087] FIGS. 3, 4, and 5 illustrate exemplary implementations of
the disclosed embodiments. More particularly, FIG. 3 illustrates a
conductor layer 12 having contact points at the top right and
bottom left of the heating system. Further illustrated are discreet
heater elements 18a of the resistive layer 18, shown in the blow up
of FIG. 3.
[0088] FIG. 4 illustrates an additional exemplary implementation of
a conductive 12 and resistive layer 18 heating system. FIG. 5
illustrates an additional embodiment, in which the current choke
point 502 of FIG. 4 is remedied by enhancements in the size of the
conductive layer 12 associated with the contact pads at the top of
the device. Of note, each of the embodiments of FIGS. 3, 4, and 5
illustrate a dielectric layer 22 printed over the conductive 12 and
resistive layers 18, with the contact points extending beyond the
dielectric layer 22 to allow for the interconnections 54 discussed
herein.
[0089] FIG. 6 illustrates an exemplary implementation of the
heating system 10 of FIG. 5 enclosed in an encapsulation layer 32.
As noted throughout, the encapsulation layer 32 may protect the
heating system 10 from environmental conditions.
[0090] FIG. 7 illustrates an exemplary implementation in which the
heating system 10 has been laminated to a textile 702. Available
textiles may include, by way of non-limiting example, nylons,
cottons, or the like.
[0091] FIG. 8 is a flow diagram illustrating an exemplary method
800 of providing a conformable heater. At step 802, an ink set is
inter-matched for use to print compatible ink layers within the ink
set, and is matched to a receiving organic or inorganic conformable
substrate. At step 804, a conductive layer formed of at least one
ink from the ink set is printed on the substrate.
[0092] At step 806, a resistive layer is printed from the ink set,
wherein the resistive layer provides at least a plurality of
heating elements in electrical communication with the conductive
layer. At step 808, a dielectric layer is printed from the ink set
in order to insulate the conductive and resistive layers.
[0093] At optional step 810, the substrate having at least the
conductive layer and the resistive layer printed thereon is at
least partially encapsulated. At optional step 812, one or more
sensors associated with the operation of the heater may be
integrated with and/or printed on the substrate.
[0094] At step 814, the heater is integrated with a wearable or a
bag. Integrating may be by sewing, lamination, adhesion, or any
like methodology, including printing upon the bag. Moreover, at
step 816, the heater may be connectively associated with one or
more driver circuits having control systems communicative
therewith, and with one or more power source connections to allow
for power to be supplied to the heating elements via the conductive
layer. By way of example, step 816 may include the printing or
other manner of interconnecting of one or more electrical
interconnections to the heater.
[0095] FIG. 9 is a flow diagram illustrating a method 900 of using
a conformable heater system. In the illustration, the conformable
heater may be associated with a power source at step 902. This
association may include a permanent association, such as via
recharging of a permanently embedded battery, or a removable
association, such as wherein an external power source, such as a
battery, a mobile device, or the like, may be removably associated
with the heater.
[0096] At step 904, the driver circuit that delivers power from the
power source to the heater may be variably controlled. Optionally,
at step 904a, wireless control may be via a wireless connection,
such as from a mobile device to the driver circuit. This wireless,
or a wired, connection may be controllable using a user interface
provided by an "app" on the mobile device, by way of non-limiting
example. The control provided thereby may be automated based on
predetermined triggers or operational limitations, manual, or a
combination thereof. Wireless control may be provided over any
known type of wireless interface.
[0097] Optionally, at step 904b, wired control may be via a wired
connection from a mobile device to the driver circuit, such as via
a micro-USB connection to the heater. As will be understood by the
skilled artisan, power may also be supplied via this connection in
alternative embodiments.
[0098] FIG. 10 illustrates an exemplary heater base, such as a
fluid bag 1002, such as a medical fluid bag 1002, for fully
containing one or more fluids within the bag between opposing plies
1004, 1006 of the bag. The fluid contained within the bag may be,
for example, blood or saline solution. Of course, in embodiments,
other fluids or gases may reside within the "bag", such as air in a
wearables embodiment. The plies 1004, 1006 may be sealed together
to form a liquid (and/or gas) tight bag via any methodology known
in the art.
[0099] In the illustrated embodiment, one ply 1004 of the bag may
have a printed heater 1008 associated therewith, as discussed
throughout, on an outward facing aspect 1004a of that first ply
1004 of the bag, and a sensing circuit 1010 comprising a sensing
chip 1012 printed on an outward face 1006a of the opposing ply 1006
of the fluid bag. In the illustrated embodiment, the IC chip 1012
may be a temperature sensor, the sensing circuit 1010 may be a
temperature sensing circuit, and the sensing circuit 1010 may
include one or more inputs and outputs 1020 that may read data,
write data, and/or connectively associate with power and/or with at
least one network, such as via wired or wireless interface.
[0100] In the illustrated embodiment, either or both of the heating
circuit 1008 and the sensing circuit 1010 may be printed circuits,
and may be printed directly onto the fluid bag 1002, or may be
printed on a separate substrate (not shown) that is then adhered to
the fluid bag 1002, such as by lamination or epoxy. Associated with
the sensing circuit side 1006a of the fluid bag 1002 may be a
printed antenna 1024, such as an RFID or NFC antenna, by way of
non-limiting example, and the printed sensing circuit 1010 may
include one or more chip sets 1012, or may include one or more
inputs or outputs from or to one or more off-bag chip sets.
[0101] The sensor circuit 1010 provided may be a printed fluid
level sensor circuit, by way of non-limiting example.
Alternatively, the sensor circuit 1010 provided may be one or more
printed or laminated temperature sensor circuits, by way of
non-limiting example. Yet further, the printed sensor circuit 1010
provided may be a combination temperature sensor and level sensing
circuit, which may or may not be associated with one or more other
sensing circuits for sensing additional characteristics of fluid
within the bag 1002.
[0102] The sensing circuit 1010 may be communicatively associated,
such as via one or more networks and network connections (such as
using antenna 1024), with one or more off-bag "apps" or
applications, which may provide a human machine interface into data
sensed by the printed sensing circuit 1010. This app or application
may be provided, by way of nonlimiting example, on one or more
mobile devices, desktop or laptop computers, dedicated medical
monitoring consoles, or the like. Data may be provided from the
sensing circuit to the one or more applications by a wire or
wirelessly, such as using the printed RF or NFC antenna 1024
discussed above.
[0103] FIGS. 11A, 11B, 11C and 11D illustrate a plurality of
alternative printed heater data circuit designs 1008a, 1008b,
1008c, 1008d for physical association with one ply 1006 of the
fluid bag 1002. More particularly, FIGS. 11A and 11B illustrate
circuit designs 1008a, 1008b for fixed resistance heaters, while
FIGS. 11C and 11D illustrate exemplary circuit designs 1008c, 1008d
for so-called "railroad pattern" heaters in which even heating and
self-limiting temperature are provided. As discussed throughout,
the printed heater 1008 may be directly associated with a printed
layer on the bag, such as a base resistive layer, or may be printed
on a substrate which is associated with a bag after printing of the
heater. In either of said circumstances, various inks apparent to
those skilled in the art may be employed for use in the heater 1008
and/or in the sensor circuit 1010, such as Henkel PTC 120.degree.
C. carbon for the resistive layer, EMS CL-1036 Silver for the
conductive layer, and Henkel PF 455B Green for the dielectric
layer, by way of nonlimiting example. Further and as will be
understood, the printing processes performed in the embodiments may
necessarily include drying, pre-shrinking, and/or curing steps,
such as UV curing steps, as will be apparent to the skilled artisan
in light of the discussion herein.
[0104] FIG. 12 is an exemplary illustration of a sensor (and data
logging/sending circuit 1010 that may be printed on a ply 1006 of
the bag that opposes the heating ply 1004. In the illustration of
FIG. 12, a thermocouple circuit 1202 may be printed directly onto
the bag 1002 and/or otherwise bonded to the bag 1002, such as using
conductive epoxy, in order to partially provide a temperature
sensing circuit 1010. More particularly, carbon strips 1202a,
1202b, . . . may be screen printed onto the bag and conductively
bonded to lead wires that lead off-bag and allow for reading of the
temperature of fluid within the bag 1002. Of note, for the
embodiment illustrated in FIG. 12 and other sensing embodiments
discussed herein, each off-bag data "reading" system may be
associated with a single medical bag, or multiple fluid bags,
wherein multiple fluid bags may be read, and accordingly data
received therefrom, by a single "master" reading device which may
then provide output data of the sensing to the human machine
interface application discussed throughout.
[0105] In an alternative embodiment, FIGS. 13A and 13B illustrate
printed circuit layouts for sensor circuits 1010e, 1010f for
association with a fluid bag 1002. In each illustration, silver ink
may be used for, foe example, two different conductive layers, and
as shown designs for sensor circuits 1010e, 1010f may include two
different dielectric layers which may comprise two different
printed inks. Also included in the illustration are two alternative
antennas 1024a, 1024b that allow for the illustrated sensing
circuits 1010e, 1010f to communicate off-bag.
[0106] Significantly, as discussed throughout, and as illustrated
with particularity in FIGS. 13A and 13B, the sensor circuit 1010e,
1010f may be printed to the bag 1002 layer by layer. Accordingly,
the sensor circuit 1010 of the embodiments comprises an ink set
having particular characteristics, both in relation to the bag 1002
or print substrate, and in relation to the other inks within the
ink set.
[0107] By way of nonlimiting example, these characteristics may
include at least the ability for any ink layer that must be
associated with the bag to be comprised of an ink suitable to grip
to the material of which the bag is constituted. Alternatively, the
base layer/substrate of the sensing circuit print may be suitable
to associate with an epoxy that will also permanently adhere to the
outer surface of the bag ply. Additionally, each successive layer
of ink must adhere in the proper manner to both the ink layer below
and, in circumstances where necessary, the ink layer to be provided
above that sequential layer.
[0108] Further, environmental factors must not adversely affect the
performance of each layer of the ink set. For example, bag "sweat",
i.e., condensation, must not adversely affect any ink that will be
printed or adhered in direct physical contact with the bag.
Further, external factors must not affect the electrical
interaction between layers to cause any undesired electrical
interference or interaction. Of course, one or more protection
layers may be printed over or below the circuit or any layer of the
circuit, but, in the same manner as is discussed above, such
protective layers must comport with each layer of the ink set
placed below and above, and must not cause unwanted interactions or
circuit decay. In particular embodiments, ink sets may include any
of a variety of dielectric inks, such as those discussed
throughout, and conductive ink layers, such as the copper and
silver inks discussed throughout.
[0109] In the illustration of FIG. 13, print widths may be
carefully monitored and controlled, such as will be apparent to the
skilled artisan in light of the discussion herein. For example,
conductive, i.e., silver, trace widths may vary in accordance with
Table 1, provided immediately below:
TABLE-US-00001 TABLE 1 Screen Design Actual Width Printed width
Percent Area (.mu.m) (.mu.m) (.mu.m) spread Antenna 635 616.63 .+-.
4 646.26 .+-. 5 4.8% Large 500 485.26 .+-. 9 508.97 .+-. 7 4.9%
Small 250 239.44 .+-. 5 266.30 .+-. 6 2.9%
[0110] FIGS. 14A, 14B, and 14C illustrate, by way of nonlimiting
example, a human machine interface app/application 1402 as
discussed throughout. In the application illustrated in FIG. 14,
the application is associated with a mobile device 1404, such as a
smart phone. As shown, the sensing circuit in the illustrated
embodiment is a temperature sensing circuit, and a user may have a
variety of options available to start, stop, clear, or reset the
temperature sensing in association with one or more fluid bags.
Other options may additionally be available to the user, such as
changes in temperature measurement, a history of measurements over
a given time period, such as may be a searchable time period, and
the like. Further, and as illustrated with particularity in FIGS.
14B and 14C, temperature data may be provided in numeric format, or
graphically, by way of nonlimiting example, and over one or more
predetermined or selected time frames.
[0111] As will be appreciated by the skilled artisan, rather than
associate particular filtering with the printed sensing circuit or
firmware discussed herein, adjustment algorithms may be included in
the application illustrated in FIG. 14, or in similar off-bag,
remote, and/or human machine interface applications. For example,
adjustment algorithms may account for the thickness or makeup of
particular brands of fluid bags, particular heating circuits that
may be associated with the fluid bag, or the like, by way of
nonlimiting example.
[0112] As discussed throughout, and as illustrated in FIGS. 15 and
16, one or more additional protective layers 1502 may be provided
over the sensing circuit 1010. Such protective outermost layers may
be similar to those discussed above with respect to protecting a
heating circuit printed on the other ply of the bag. Such a
protective layer 1502 may be formed of a dielectric, by way of
nonlimiting example, and may thereby prevent oxidation of the
conductive layers 1504 of the sensing circuit, may protect the
circuit, traces, and electrical connections from physical damage,
and may reinforce the proper conductive nature of the traces,
particularly at the edges of encapsulated areas.
[0113] More particularly, specific and/or more extensive protective
printed layers may be provided in association with particularly
delicate portions of the printed sensing circuit, and/or in
association with particularly complex applications for circuit
1010. By way of example, because of variations in bag curvature
when an intravenous (IV) bag is filled versus empty, a more rigid
secondary under layer or cover layer 1702 may be provided in
association with the printed antenna 1024 of the sensing circuit
1010. This may keep the antenna 1024 as flat as possible, thereby
maximizing communication integrity and read range for the printed
sensing circuit 1010. Such embodiments are illustrated, by way of
nonlimiting example, in FIGS. 17A, 17B and 17C.
[0114] In addition to the temperature sensing circuit discussed
throughout, also referenced above is a fluid level sensing circuit.
Such a circuit may monitor fluid levels within the bag and may
thereby allow for automated indications of the need for bag
replacement and the like. Such sensing, although not illustrated
with particularity herein, may have access thereto also provided
through the human machine interface application discussed
throughout.
[0115] A fluid level sensing circuit may comprise, by way of
example, a self-capacitive sensing circuit, such as may include a
plurality of silver traces used to measure bag capacitance at
various locations across the bag. Additionally and alternatively,
rather than capacitive strips, capacitor buttons may be placed
along particular areas of a ply of the fluid bag. Each button may
act as a capacitive detector to indicate whether the fluid has
reached that level. Of course, other methods of printing level
sensing circuits, such as capacitive level sensors, will be
apparent to those skilled in the art in light of the discussion
herein and may be subjected to the ink set limitations discussed
throughout.
[0116] By way of nonlimiting example, a sensing circuit 1010 may
include one or more conductive inks, such as EMS CL-1036 Silver
ink, and one or more dielectric layer inks, such as EMS DL-7540
Blue. Conductive adhesives for certain of the layers may be
comprised of any conductive adhesive known to those skilled in the
art for incorporation into the instant embodiments, such as Henkel
QML516LE, Henkel 2030 SC, and Henkel SL-5421. The encapsulating
layer may be comprised of any known principle material, such as
laminate VE 529610.
[0117] Further, the descriptions of the disclosure are provided to
enable any person skilled in the art to make or use the disclosed
embodiments. Various modifications to the disclosure will be
readily apparent to those skilled in the art, and the generic
principles defined herein may be applied to other variations
without departing from the spirit or scope of the disclosure. Thus,
the disclosure is not intended to be limited to the examples and
designs described herein, but rather is to be accorded the widest
scope consistent with the principles and novel features disclosed
herein.
* * * * *