U.S. patent application number 10/884900 was filed with the patent office on 2004-12-02 for fluid ejector apparatus and methods.
Invention is credited to Ayres, James W., Dunfield, John Stephen.
Application Number | 20040241008 10/884900 |
Document ID | / |
Family ID | 32069399 |
Filed Date | 2004-12-02 |
United States Patent
Application |
20040241008 |
Kind Code |
A1 |
Dunfield, John Stephen ; et
al. |
December 2, 2004 |
Fluid ejector apparatus and methods
Abstract
A fluid ejector head, includes a fluid ejector body adapted to
be inserted into an opening of an enclosing medium having an
interior surface, and at least one nozzle disposed on the fluid
ejector body. The fluid ejector head further includes, a fluid
ejector actuator in fluid communication with the at least one
nozzle, wherein activation of the fluid ejector actuator ejects a
fluid through the at least one nozzle at controlled locations onto
the interior surface of the enclosing medium.
Inventors: |
Dunfield, John Stephen;
(Corvallis, OR) ; Ayres, James W.; (Corvallis,
OR) |
Correspondence
Address: |
HEWLETT-PACKARD COMPANY
Intellectual Property Administration
P.O. Box 272400
Fort Collins
CO
80527-2400
US
|
Family ID: |
32069399 |
Appl. No.: |
10/884900 |
Filed: |
July 6, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10884900 |
Jul 6, 2004 |
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10281007 |
Oct 24, 2002 |
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6786591 |
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Current U.S.
Class: |
417/182 ;
417/572 |
Current CPC
Class: |
B41J 3/407 20130101 |
Class at
Publication: |
417/182 ;
417/572 |
International
Class: |
F04F 005/48 |
Claims
What is claimed is:
1.-46. (Canceled).
47. A method of manufacturing a fluid ejector head, comprising:
creating a fluid ejector body adapted to be inserted into an
opening of an enclosing medium, said medium having an interior
surface; forming at least one orifice on said fluid ejector body;
and creating a drop-on-demand fluid ejector actuator in fluid
communication with said at least one orifice, wherein activation of
said drop-on-demand fluid ejector actuator ejects a fluid onto a
discrete location on said interior surface of said elongated
enclosing medium.
48. The method in accordance with claim 47, wherein creating a
fluid ejector body further comprises creating a substrate having at
least one active device electrically coupled to said drop-on-demand
fluid ejector actuator.
49. The method in accordance with claim 47, further comprising:
forming a chamber layer over a substrate within said fluid ejector
body; defining side walls of at least one fluid ejection chamber
about said drop-on-demand fluid ejector actuator, said side walls
formed in said chamber layer; and creating a nozzle layer over said
chamber layer wherein said nozzle layer includes said at least one
orifice.
50. The method in accordance with claim 49, wherein creating a
nozzle layer further comprises creating a micromolded nozzle layer
having said at least one orifice.
51. The method in accordance with claim 49, wherein forming a
chamber layer further comprises forming a micromolded chamber layer
having said sidewalls of said at least one fluid ejection
chamber.
52. The method in accordance with claim 47, further comprising:
forming at least one fluid inlet channel in a substrate within said
fluid ejector body fluidically coupled to said at least one
orifice; and forming a fluid channel within said fluid ejector body
fluidically coupled to said at least one fluid inlet channel.
53. The method in accordance with claim 47, wherein creating said
drop-on-demand fluid ejector actuator further comprises creating at
least one fluid energy generating element.
54. The method in accordance with claim 53, wherein creating at
least one fluid energy generating element further comprises
creating at least one fluid energy generating element of a first
type and at least one fluid energy generating element of a second
type.
55. A fluid ejector head manufactured in accordance with the method
of claim 53.
56. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating a fluid ejector body
having a longitudinal axis, and wherein forming at least one
orifice further comprises forming at least one orifice having an
orifice ejection axis, wherein said longitudinal axis and said
orifice ejection axis form a predetermined ejection angle.
57. The method in accordance with claim 56, wherein said
predetermined angle is in the range from about minus sixty degrees
to plus sixty degrees about a fluid body normal of said fluid
body.
58. A fluid ejector head manufactured in accordance with the method
of claim 47.
59.-79. (Canceled).
80. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating said fluid ejector
body having a cylindrical portion including a diameter less than an
inside diameter of said opening of said enclosing medium.
81. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating said fluid ejector
body having cylindrical outer surface, said cylindrical outer
surface having a longitudinal axis, wherein said cylindrical outer
surface conforms to said interior surface of said enclosing
medium.
82. The method in accordance with claim 47, further comprising
creating a first fluid channel fluidically coupled to said at least
one orifice.
83. The method in accordance with claim 82, further comprising:
forming at least one second fluid orifice disposed on said fluid
ejector body; creating a second fluid channel fluidically coupled
to said at least one second fluid orifice; and creating a second
drop-on-demand fluid ejector actuator in fluid communication with
said at least one second fluid orifice, wherein activation of said
second drop-on-demand fluid ejector actuator ejects a second fluid
onto said interior surface of said enclosing medium.
84. The method in accordance with claim 83, further comprising:
forming at least one third fluid orifice disposed on said fluid
ejector body; creating a third fluid channel fluidically coupled to
said at least one third fluid orifice; and creating a third
drop-on-demand fluid ejector actuator in fluid communication with
said at least one third fluid orifice, wherein activation of said
third drop-on-demand fluid ejector actuator ejects a third fluid
material onto said interior surface of said enclosing medium.
85. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating said fluid ejector
body having a curvilinear cross-sectional shape.
86. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating said fluid ejector
body having a polygonal cross-sectional shape.
87. The method in accordance with claim 47, wherein forming said at
least one orifice further comprises forming multiple orifices.
88. The method in accordance with claim 87, wherein forming said
multiple orifices further comprises forming said multiple orifices
in a helical configuration.
89. The method in accordance with claim 87, wherein forming said
multiple orifices further comprises forming said multiple orifices
in a single helix configuration.
90. The method in accordance with claim 87, wherein forming said
multiple orifices further comprises forming said multiple orifices
in a straight configuration.
91. The method in accordance with claim 87, wherein forming said
multiple orifices further comprises forming said multiple orifices
in a staggered configuration.
92. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating said fluid ejector
body having a conformal outer surface conforming to said interior
surface.
93. The method in accordance with claim 47, wherein creating said
fluid ejector body further comprises creating a fluid ejector body
having a fluid ejecting area wherein said fluid ejecting area
conforms to a deposition area of said interior surface of said
enclosing medium over which fluid is to be deposited.
Description
BACKGROUND
[0001] Description of the Art
[0002] Over the past decade, substantial developments have been
made in the micro-manipulation of fluids in fields such as
electronic printing technology using inkjet printers. Currently
there is a wide variety of highly-efficient inkjet printing systems
in use, which are capable of dispensing ink in a rapid and accurate
manner onto paper sheets or other relatively flat media such as
envelopes or labels.
[0003] Typically, an inkjet printing system utilizes a platen to
which a paper sheet or other relatively flat and flexible medium is
transported by friction utilizing various motors, gears, wheels,
shafts and mounts. This medium transport mechanism, typically,
provides the movement enabling the medium to be acquired from a
tray and then advanced through a print zone by pushing, pulling, or
carrying the medium. The print zone typically locates the medium
relative to the printhead. A nearly flat print zone is, typically,
utilized because the two-dimensional extent of typical nozzle
layouts would result in varying firing distances if the medium or
medium support has to much curvature. A carriage holding one or
more print cartridges, having one or more fluid ejector heads, is,
typically, supported by a slide bar, or similar mechanism within
the system, and physically propelled along the slide bar to allow
the carriage to be translationally reciprocated or scanned back and
forth across the medium. When a swath of ink dots has been
completed, the medium is moved an appropriate distance along the
medium sheet axis, in preparation for the next swath.
[0004] The ability, to utilize fluid ejectors and fluid dispensing
systems, to dispense discrete deposits of a material onto the
surface of media of various shapes and flexibility, in specified
locations, would open up a wide variety of applications that are
currently impractical.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1a is a perspective view of a fluid ejector head
according to an embodiment of the present invention;
[0006] FIG. 1b is a perspective view of a fluid ejector head
according to an alternate embodiment of the present invention;
[0007] FIG. 2a is an isometric cross-sectional view of a fluid
ejector body according to an alternate embodiment of the present
invention;
[0008] FIG. 2b is a perspective view of a portion of the fluid
ejector body shown in FIG. 2a according to an embodiment of the
present invention;
[0009] FIG. 3 is a cross-sectional view of a fluid ejector body
according to an alternate embodiment of the present invention;
[0010] FIG. 4 is a cross-sectional view of a fluid ejector body
according to an alternate embodiment of the present invention;
[0011] FIG. 5 is a cross-sectional view of a fluid ejector body
according to an alternate embodiment of the present invention;
[0012] FIG. 6a is a perspective view of a fluid ejection cartridge
according to an embodiment of the present invention;
[0013] FIG. 6b is a perspective view of a fluid dispensing system
according to an embodiment of the present invention;
[0014] FIG. 7 is a flow diagram of a method of manufacturing a
fluid ejector head according to an embodiment of the present
invention;
[0015] FIG. 8 is a flow diagram of a method of using a fluid
dispensing system according to an embodiment of the present
invention;
[0016] FIG. 9a is a perspective view of an article made using an
embodiment of the present invention;
[0017] FIG. 9b is a perspective view of an article made using an
embodiment of the present invention;
[0018] FIG. 9c is a perspective view of an article made using an
embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Referring to FIG. 1a, an embodiment of the present invention
is shown in a perspective view. In this embodiment, fluid ejector
head 100 includes fluid ejector body 120 adapted to be inserted
into enclosing medium opening 108. Fluid ejector head 100 further
includes nozzles 130 disposed on fluid ejector body 120 and
fluidically coupled to fluid channel 140. Fluid ejector actuator
150 is in fluid communication with nozzles 130. Activation of fluid
ejector actuator 150 ejects a fluid onto a predetermined location
onto interior surface 110 of enclosing medium 106.
[0020] For purposes of this description and the present invention,
the term enclosing medium may be any solid or semi-solid material
object with a shape, having a substantially fixed form, including
an inside, or interior, surface and an outer, or exterior, surface.
The term substantially fixed form is used to imply permanence of
the interior surface of the object not of the shape of the object.
For example, a bag may change shape depending on whether it is open
or closed, however, the existence of the interior surface remains
whether open or closed. In addition, the substantially fixed form
also includes at least one opening having a cross-sectional area
less than the maximum cross-sectional area obtainable for that
shape. The enclosing medium may have rectangular parallelepiped,
cylindrical, ellipsoidal, or spherical shapes just to name a few
simple geometric shapes that may be utilized. For example,
enclosing medium 106 may be a vial, a bottle, a capsule, a box, a
bag, or a tube to name a few articles that may be utilized. In
alternate embodiments, as shown in FIG. 1b, enclosing medium 106
may include a bottom surface such as a vial or gelatin capsule. In
addition fluid ejector head 100' may also include nozzles providing
ejection of the fluid onto bottom interior surface 109, as well as
the side interior surface 110', of the capsule as shown in FIG.
1b.
[0021] In this embodiment fluid ejector body 120 includes multiple
bores or nozzles 130, the actual number shown in FIGS. 1a and 1b is
for illustrative purposes only. The number of nozzles utilized
depends on various parameters such as the particular fluid or
fluids to be dispensed, the particular deposits to be generated,
and the particular size of the enclosing medium utilized. In this
embodiment, either fluid ejector body 120 or enclosing medium 106
or both are rotatable about the longitudinal axis 112 of enclosing
medium 106 providing the ability to dispense fluid in a
two-dimensional array on the interior surface of the enclosing
medium. Fluid ejector head 100 provides control of fluid deposits
by dispensing the fluid in discrete amounts on the inside of an
enclosing medium in a controlled manner.
[0022] It should be noted that the drawings are not true to scale.
Further, various elements have not been drawn to scale. Certain
dimensions have been exaggerated in relation to other dimensions in
order to provide a clearer illustration and understanding of the
present invention.
[0023] In addition, although some of the embodiments illustrated
herein are shown in two dimensional views with various regions
having depth and width, it should be clearly understood that these
regions are illustrations of only a portion of a device that is
actually a three dimensional structure. Accordingly, these regions
will have three dimensions, including length, width, and depth,
when fabricated on an actual device. Moreover, while the present
invention is illustrated by various embodiments, it is not intended
that these illustrations be a limitation on the scope or
applicability of the present invention. Further it is not intended
that the embodiments of the present invention be limited to the
physical structures illustrated. These structures are included to
demonstrate the utility and application of the present invention to
presently preferred embodiments.
[0024] Fluid ejector body 120, in this embodiment, is a tubular
shaped structure having an outside diameter less than the inside
diameter of enclosing medium opening 108, such that fluid ejector
body 120 is insertable into enclosing medium opening 108, along
longitudinal axis 112, of enclosing medium 106. In this embodiment,
fluid ejector body 120 also includes a fluid ejector body
longitudinal axis 111 that is aligned with longitudinal axis 112 of
enclosing medium 106. In alternate embodiments, depending on
various parameters such as the shape of the enclosing medium and
the fluid ejector body, the fluid ejector body longitudinal axis
may not be in alignment with the longitudinal axis of the enclosing
medium. Fluid ejector body 120 may utilize any ceramic, metal, or
plastic material capable of forming the appropriate sized tubular
shape. Fluid ejector actuator 150 may be any device capable of
imparting sufficient energy to the fluid either in fluid channel
140 or in close proximity to nozzles 130. For example, compressed
air actuators, such as utilized in an airbrush, or
electro-mechanical actuators or thermal mechanical actuators may be
utilized to eject the fluid from nozzles 130.
[0025] An exemplary embodiment of a fluid ejector head is shown in
an isometric cross-sectional view in FIG. 2a. In this embodiment,
fluid ejector head 200 includes fluid ejector body 220 wherein at
least a portion of the body has a rectangular cross-section. In
alternate embodiments, fluid ejector body may have a parallelepiped
structure. In addition, fluid ejector body 220 also includes fluid
body longitudinal axis 211 projecting in and out of the cross
sectional view. Fluid ejector body 220 is adapted to be inserted
into an opening of an enclosing medium and is rotatable within the
enclosing medium. In addition, nozzle 230 has an ejection axis 231
defining the general direction in which drops are ejected from
fluid ejector body 220. Fluid body longitudinal axis 211 and nozzle
ejection axis 231 form predetermined ejection angle 218 (see FIG.
2b). In this embodiment, nozzle ejection axis 231 may be aligned at
an angle between 0.degree. and 60.degree. degrees from fluid body
normal 211' of fluid body longitudinal axis 211 as shown in a
perspective view in FIG. 2b. In alternate embodiments, nozzle
ejection axis 232 is aligned at an angle between 0.degree. and
45.degree., and more preferably nozzle ejection axis 232 is
substantially perpendicular to fluid body longitudinal axis 211. In
addition, ejection angles 231' and 231" illustrate that the angle
may be either in a positive or in a negative direction relative to
fluid body normal 211'.
[0026] Fluid ejector head 200 further includes fluid ejector
actuator 250, chamber layer 266, fluid body housing 280, and nozzle
layer 236. In this embodiment, substrate 222 is a portion of a
silicon wafer. In alternate embodiments, other materials may also
be utilized for substrate 222, such as, various glasses, aluminum
oxide, polyimide substrates, silicon carbide, and gallium arsenide.
Accordingly, the present invention is not intended to be limited to
those devices fabricated in silicon semiconductor materials. In
this embodiment, fluid body housing 280 and substrate 222 form
fluid channel 240. Fluid inlet channels 241 are formed in substrate
222, and provide fluidic coupling between fluid channel 240 and
fluid ejection chamber 272.
[0027] Fluid energy generating element 252 is disposed on substrate
222 and provides the energy impulse utilized to eject fluid from
nozzle 230. As described above, fluid ejector actuator 250 may be
any element capable of imparting sufficient energy to the fluid to
eject it from nozzle 230. In this embodiment, fluid ejector
actuator 250 includes fluid energy generating element 252, which is
a thermal resistor. In alternate embodiments, other fluid energy
generating elements such as piezoelectric, flex-tensional,
acoustic, and electrostatic generators may also be utilized. For
example, a piezoelectric element utilizes a voltage-pulse to
generate a compressive force on the fluid resulting in ejection of
a drop of the fluid. In still other embodiments, fluid energy
generating element 252 may be located some distance away, in a
lateral direction, from nozzle 230. The particular distance will
depend on various parameters such as the particular fluid being
dispensed, the particular structure of chamber 272, and the
structure and size of fluid channel 240, to name a few
parameters.
[0028] The thermal resistor is typically formed as a tantalum
aluminum alloy utilizing conventional semiconductor processing
equipment. In alternate embodiments, other resistor alloys may be
utilized such as tungsten silicon nitride, or polysilicon. The
thermal resistor typically is connected to electrical inputs by way
of metallization (not shown) on the surface of substrate 222.
Additionally, various layers of protection from chemical and
mechanical attack may be placed over the thermal resistor, but are
not shown in FIG. 2 for clarity. Substrate 222 also includes, in
this embodiment, active devices such as one or more transistors
(not shown for clarity) electrically coupled to fluid energy
generating element 252. In alternate embodiments, other active
devices such as diodes or memory logic cells may also be utilized,
either separately or in combination with the one or more
transistors. In still other embodiments, what is commonly referred
to as a "direct drive" fluid ejector head, where substrate 222 may
include fluid ejector generators without active devices, may also
be utilized. The particular combination of active devices and fluid
energy generating elements will depend on various parameters such
as the particular application in which fluid ejector head 200 is
used, and the particular fluid being ejected to name a couple of
parameters.
[0029] In this embodiment, an energy impulse applied across the
thermal resistor rapidly heats a component in the fluid above its
boiling point causing vaporization of the fluid component resulting
in an expanding bubble that ejects fluid drop 214 as shown in FIG.
2a. Fluid drop 214 typically includes droplet head 215, drop-tail
216 and satellite-drops 217, which may be characterized as
essentially a fluid drop. In this embodiment, each activation of
energy generating element 252 results in the ejection of a precise
quantity of fluid in the form of essentially a fluid drop; thus,
the number of times the fluid energy generating element is
activated controls the number of drops 214 ejected from nozzle 230
(i.e. n activations results in essentially n fluid drops). Thus,
fluid ejector head 200 may generate deposits of discrete droplets
of a fluid, including a solid material dissolved in one or more
solvents or suspended or dispersed in the fluid, onto a discrete
predetermined location on the interior surface of an enclosing
substrate
[0030] The drop volume of fluid drop 214 may be optimized by
various parameters such as nozzle bore diameter, nozzle layer
thickness, chamber dimensions, chamber layer thickness, energy
generating element dimensions, and the fluid surface tension to
name a few. Thus, the drop volume can be optimized for the
particular fluid being ejected as well as the particular
application in which the enclosing medium will be utilized. Fluid
ejector head 200 described in this embodiment can reproducibly and
reliably eject drops in the range of from about five femtoliters to
about 10 nanoliters depending on the parameters and structures of
the fluid ejector head as described above. In alternate
embodiments, fluid ejector head 200 can eject drops in the range
from about 5 femtoliters to about 1 microliter. In addition,
according to other embodiments, multiple fluid ejector heads 200
may be ganged together to form polygonal structures. For example,
two fluid ejector heads 200 may be formed back to back providing
the ability to dispense two different fluids so that, one set of
fluid ejector heads may dispense ink, and another set of fluid
ejector heads may dispense a sealant or protective material to
cover or coat the dispensed ink. A second example, utilizes
multiple sets of fluid ejector heads to eject multiple different
fluids such as color inks with or without the use of a sealant or
protective material. The term fluid includes any fluid material
such as inks, adhesives, lubricants, chemical or biological
reagents, as well as fluids containing dissolved or dispersed
solids in one or more solvents. Further, fluid ejector head 200 may
also contain a fluid that is a mixture of materials providing
multiple functions and thus various combinations are possible, such
as one set of fluid ejector heads ejecting an ink and protective
material mixed together, and another set ejecting just an ink.
[0031] Chamber layer 266 is selectively disposed over the surface
of substrate 222. Sidewalls 268 define or form fluid ejection
chamber 272, around energy generating element 252, so that fluid,
from fluid channel 240 via fluid inlet channels 241, may accumulate
in fluid ejection chamber 272 prior to activation of energy
generating element 252 and expulsion of fluid through nozzle or
orifice 230 when energy generating element 252 is activated. Nozzle
or orifice layer 236 is disposed over chamber layer 266 and
includes one or more bores or nozzles 230 through which fluid is
ejected. In alternate embodiments, depending on the particular
materials utilized for chamber layer 266 and nozzle layer 236, an
adhesive layer (not shown) may also be utilized to adhere nozzle
layer 236 to chamber layer 266. According to additional
embodiments, chamber layer 266 and nozzle layer 236 are formed as a
single integrated chamber nozzle layer. Chamber layer 266,
typically, is a photoimagible film that utilizes photolithography
equipment to form chamber layer 266 on substrate 222 and then
define and develop fluid ejection chamber 272. The nozzles formed
along longitudinal axis 211 may be in a straight line or a
staggered configuration depending on the particular application, in
which fluid ejector head 200 is utilized, a staggered configuration
is illustrated in FIG. 2b.
[0032] Nozzle layer 236 may be formed of metal, polymer, glass, or
other suitable material such as ceramic. In this embodiment, nozzle
layer 236 is a polyimide film. Examples of commercially available
nozzle layer materials include a polyimide film available from E.
I. DuPont de Nemours & Co. sold under the name "Kapton", a
polyimide material available from Ube Industries, LTD (of Japan)
sold under the name "Upilex." In an alternate embodiment, the
nozzle layer 236 is formed from a metal such as a nickel base
enclosed by a thin gold, palladium, tantalum, or rhodium layer. In
other alternative embodiments, nozzle layer 236 may be formed from
polymers such as polyester, polyethylene naphthalate (PEN), epoxy,
or polycarbonate.
[0033] An alternate embodiment of a fluid ejector head is shown in
a cross-sectional view in FIG. 3. In this embodiment, fluid ejector
head 300 includes fluid ejector body 320, wherein at least a
portion of the body has a cylindrical cross-sectional shape,
including fluid body longitudinal axis 311 projecting in and out of
the cross sectional view. In alternate embodiments, fluid ejector
body 320 may have a portion having a curvilinear shape. Fluid
ejector head 300 further includes fluid ejector actuator 350,
second fluid ejector actuator 354, and third fluid ejector actuator
358 disposed on fluid ejector body 320. Although the fluid ejector
actuators are disposed under the nozzles in this embodiment, in
alternate embodiments, the fluid ejector actuators may be
positioned some lateral distance away from the nozzles. The
particular distance will depend on various parameters such as the
particular fluid being dispensed, the particular structure of the
chambers, and the structure and size of the fluid channels, to name
a few parameters. Fluid channel separator 346 is attached to
substrate 322 and separates fluid ejector head 300 into three
sections: fluid section 323, second fluid section 324, and third
fluid section 325. In this embodiment, fluid channel 340 is formed
by fluid channel separator portions 346' and substrate 322; second
fluid channel 342 is formed by fluid channel separator portions
346" and substrate 322; and third fluid channel 344 is formed by
fluid channel separator portions 346'" and substrate 322.
[0034] Fluid inlet channels 341 provide fluidic coupling between
fluid channel 340 and chamber 372, and are formed in substrate 322
within fluid section 323. Fluid inlet channels 343 and 345 provide
fluidic coupling between fluid channels 342 and 344 and chambers
374 and 376 respectively. Fluid energy generating element 352 is
disposed on substrate 322 and provides the energy impulse utilized
to eject fluid from nozzle 330. Fluid energy generating elements
356 and 360 provide the energy impulses utilized to eject fluid
from nozzles 332 and 334 respectively. In this embodiment, fluid
energy generating elements 352, 356, and 360 are thermal resistors
that rapidly heat a component in the fluid above its boiling point
causing vaporization of the fluid component resulting in ejection
of a drop of the fluid. In alternate embodiments, other fluid
energy generating elements such as piezoelectric, flex-tensional,
acoustic, and electrostatic generators may also be utilized. In
this embodiment, fluid energy generating elements 352, 356, and 360
eject the fluid in a substantially radial direction onto the
interior surface of the enclosing medium (not shown).
[0035] Chamber layer 366 is disposed over substrate 322 wherein
sidewalls 368' define or form a portion of fluid ejection chamber
372 in fluid section 323; sidewalls 368" form a portion of second
fluid ejection chamber 374 in second fluid section 324; and
sidewalls 368'" for a portion of fluid ejection chamber 376 in
third fluid section 325. Nozzle or orifice layer 336 is disposed
over chamber layer 366 and includes one or more bores or nozzles
330, 332, and 334 through which fluid in the three sections is
ejected. In alternate embodiments, depending on the particular
materials utilized for chamber layer 366 and nozzle layer 336, an
adhesive layer may also be utilized to adhere nozzle layer 336 to
chamber layer 366. According to additional embodiments, chamber
layer 366 and nozzle layer 336 are formed as a single layer. Such
an integrated chamber and nozzle layer structure is commonly
referred to as a chamber orifice or chamber nozzle layer.
[0036] Although FIG. 3 depicts fluid ejector body 320 separated
into three sections, alternate embodiments may utilize anywhere
from a single section to multiple sections depending on the
particular application in which fluid ejector head 300 is utilized.
For example, fluid ejector body 320 may have a single section to
eject a single fluid. In addition, the fluid chambers formed along
longitudinal axis 311 may be in a straight line, staggered
configuration, or helical configuration depending on the particular
application in which fluid ejector head 300 is utilized. In another
example, fluid ejector body 320 includes six sections having
straight, staggered, or helical configurations, providing for any
of the possible combinations of dispensing multiple fluids.
[0037] In addition to having various numbers of sections each
section may also be independently optimized for performance. For
example, the energy generating elements of each section may be
optimized for the particular fluid ejected by that section. In
addition, the dimensions of the ejection chambers and nozzles may
also be optimized for the particular fluid ejected by that section.
Further, energy generating elements as well as chamber and nozzle
dimensions within a section may also be varied providing ejection
of different drop sizes of the same fluid to be ejected from fluid
ejector head 300.
[0038] Referring to FIG. 4 an alternate embodiment of a fluid
ejector head according to the present invention is shown in a
cross-sectional view. In this embodiment, fluid ejector head 400
includes fluid ejector body 420 having a rectangular or square
tubular cross-sectional shape, including a longitudinal axis 412
projecting in and out of the cross-sectional view. Fluid ejector
head 400 further includes fluid ejector actuator 450, second fluid
ejector actuator 454, and third fluid ejector actuator 458 and
fourth fluid ejector actuator 460 disposed on fluid ejector body
420. Fluid channel separator 446 is attached to substrate 422 and
separates fluid ejector head 400 into four sections: first fluid
section 440, second fluid section 424, third fluid section 425, and
fourth fluid section 426. For example, four different fluids may be
utilized such as a black ink and three color inks. In another
example, four different reactive agents may be utilized. In still
other examples, various combinations of different fluids such as
two different bioactive agents, an ingestible ink and a protective
material to cover either the bioactive agents or ink or both may be
utilized. In this embodiment, fluid channel 440, is formed by fluid
channel separator portions 446' and substrate 422; second fluid
channel 442 is formed by fluid channel separator portions 446" and
substrate 422; third fluid channel 444 is formed by fluid channel
separator portions 446'" and substrate 422; and fourth fluid
channel 448 is formed by fluid channel separator portions 446" "
and substrate 422.
[0039] Fluid inlet channels 441 provide fluidic coupling between
fluid channel 440 and fluid ejection chamber 472, and are formed in
substrate 422 within fluid section 423; fluid inlet channels 443
provide fluidic coupling between fluid channel 442 and fluid
ejection chamber 474; fluid inlet channels 445 provide fluidic
coupling between fluid channel 444 and fluid ejection chamber 476;
and fluid inlet channels 449 provide fluidic coupling between fluid
channel 448 and fluid ejection chamber 473. Fluid energy generating
elements 452, 456, 459, and 463 are disposed on substrate 422 and
provide the energy impulse utilized to eject fluid from nozzles
430, 432, 434, and 436 respectively. As described in previous
embodiments, fluid energy generating elements 452, 456, 459, and
463 may be any element capable of imparting sufficient energy to
the fluid to eject it from nozzles.
[0040] Chamber orifice layer 478 is disposed over substrate 422
wherein sidewalls 468 define or form a portion of fluid ejection
chamber 472; sidewalls 469 form a portion of fluid ejection chamber
474; sidewalls 470 form a portion of fluid ejection chamber 473;
and sidewalls 471 form a portion of fluid ejection chamber 476.
Chamber orifice layer 478 also includes one or more bores or
nozzles 430, 432, 434, and 436 respectively in each section through
which fluid is ejected.
[0041] Although FIG. 4 depicts fluid ejector body 420 separated
into four sections, alternate embodiments, may utilize even more
sections depending on the particular application in which fluid
ejector head 400 is utilized. For example, fluid ejector body 420
may have five or six sections, or other number of sections, forming
a pentagonal or hexagonal, or polygonal shape respectively,
providing for any of the various possible combinations of
dispensing multiple fluids, depending on the particular application
in which fluid ejector head 400 is utilized. As described above the
fluid chambers and nozzles formed along longitudinal axis 412 may
be in a straight line, or staggered configuration depending on the
particular application in which fluid ejector head 400 is utilized.
In addition, as also described above, each section as well as
chambers, nozzles and energy generating elements may also be
independently optimized for performance.
[0042] Referring to FIG. 5 an alternate embodiment of a fluid
ejector head of the present invention is shown in a cross-sectional
view. In this embodiment, fluid ejector head 500 includes fluid
ejector body 520 having a rectangular shape, including fluid body
longitudinal axis 511 projecting in and out of the cross sectional
view. In addition, fluid ejector head 500 includes a combination of
different types of fluid ejector actuators. First and second fluid
ejector actuators 550 and 551 are of a first type, and third and
fourth fluid ejector actuators 554 and 558 are of a second type. In
this embodiment, first and second fluid ejector actuators 550 and
551 are piezoelectric transducers 552 and 553, while third and
fourth fluid ejector actuators 554 and 558 are thermal resistor
energy generating elements 556 and 560 respectively.
[0043] Fluid section 523 includes diaphragm 562 attached to
substrate 522 and piezoelectric transducer 552, and fluid section
526 includes diaphragm 563 attached to substrate 523 and
piezoelectric transducer 553. A voltage pulse applied across either
piezoelectric transducer 552 or 553 results in a physical
displacement of the piezoelectric transducer and the diaphragm
generating a compressive force on the fluid located in either fluid
ejection chambers 570 or 572 resulting in ejection of a drop of the
fluid from either nozzle 530 or 536. Chamber orifice layer 578 is
disposed over substrates 522 and 523 wherein sidewalls 568 and 569
define or form a portion of fluid ejection chambers 570 and 572
respectively. Chamber orifice layer 578 also includes one or more
bores or nozzles 530 and 536 through which fluid is ejected. Fluid
inlet channels 541 and 543 provide fluidic coupling between fluid
channels 540 and 542 and fluid ejection chambers 570 and 572, and
are formed between substrate 522 and chamber orifice layer 578
within fluid sections 523 and 526.
[0044] Third fluid section 524 and fourth fluid section 525 are
formed by substrate 521 and channel top plate 538 of fluid ejector
body 520. In addition, substrate 521 and channel top plate 538 form
nozzles 532, and 534. These two sections form what are commonly
referred to as a "side shooter" configuration, as compared to the
"roof shooter" configuration illustrated in FIG. 2. In alternate
embodiments, substrate 521 and substrate 523 may be integrated to
form a single substrate having different energy generating elements
disposed over different portions. In addition, substrate 522 and
channel top plate 538 may also be integrated. Third fluid inlet
channel 545 provides fluidic coupling between third fluid channel
544 and third fluid ejection chamber 574. Fourth fluid inlet
channel 547 provides fluidic coupling between fourth fluid channel
546 and fourth fluid ejection chamber 576. Fluid energy generating
elements 556 and 560 are disposed on substrate521 and provide the
energy impulse utilized to eject fluid from nozzles 532 and 536
respectively.
[0045] Although the embodiment illustrated in FIG. 5 shows fluid
sections 523 and 526 having piezoelectric transducers and fluid
sections 524 and 525 having thermal resistors for ejecting a fluid,
alternate embodiments may utilize any of combination of energy
generating elements described in previous embodiments. Combining
thermal resistor "roof shooters" and side shooters in the same
fluid ejector head, or combining piezoelectric, and ultrasonic
transducers in the same fluid ejector head, are just a couple of
examples of combinations of various energy generating elements that
may be utilized. In another example, fluid ejector head 500 may
contain one section utilizing a compressed air fluid ejector
actuator, a second section utilizing piezoelectric fluid energy
generating elements, and still third and fourth sections utilizing
thermal resistor energy generating elements.
[0046] Referring to FIG. 6a an exemplary embodiment of fluid
ejection cartridge 602 of the present invention is shown in a
perspective view. In this embodiment, fluid ejection cartridge 602
includes fluid ejector head 600 fluidically coupled to fluid
reservoir 628. Fluid ejector body 620 is adapted to be inserted
into an enclosing medium opening (not shown). Fluid ejector head
600 further includes nozzles 630 disposed on fluid ejector body 620
and fluidically coupled to fluid channel 640. Fluid contained in
fluid reservoir 628 is supplied via filter 648 to fluid channel
640. In addition, fluid ejector actuator 650 is in fluid
communication with nozzles 630 so that fluid is ejected from
nozzles 630 when fluid ejector actuator is activated. In this
embodiment, fluid ejector actuator 650 is electrically coupled to
electrical connector 668 via electrical traces or wires (not
shown). In alternate embodiments, utilizing, for example,
compressed air, fluid ejector actuator 650 may be coupled, to a
fluid controller (see FIG. 6b), utilizing different connectors such
as compressed air fittings and tubing. Fluid ejector head 600 can
be any of the fluid ejector heads described in previous
embodiments.
[0047] Information storage element 664 is disposed on fluid
ejection cartridge 602 as shown in FIG. 6a. Information storage
element 664 is electrically coupled to electrical connector 668. In
alternate embodiments information storage element 664 may utilize a
separate electrical connector disposed on body 660. Information
storage element 664 is any type of memory device suitable for
storing and outputting information, to a controller, that may be
related to properties or parameters of the fluid or fluid ejector
head 600 or both. In this embodiment, information storage element
664 is a memory chip mounted to body 660 and electrically coupled
through electrical traces 670 to electrical connector 668. When
fluid ejection cartridge 602 is either inserted into, or utilized
in, a fluid dispensing system information storage element 664 is
electrically coupled to a controller (not shown) that communicates
with information storage element 664 to use the information or
parameters stored therein.
[0048] Referring to FIG. 6b an exemplary embodiment of fluid
dispensing system 604 of the present invention is shown in a
perspective view. In this embodiment, fluid dispensing system 604
includes enclosing medium tray 684 having an n.times.m array of
enclosing medium holders 686 adapted to accept insertion of
enclosing medium parts 606. Fluid dispensing system 604 further
includes an i.times.j array of fluid ejection cartridges 602 that
include fluid ejector bodies 620 adapted to be inserted into
enclosing medium openings 608. For example, a system may utilize a
tray having a 4.times.4 array of holders containing enclosing
medium parts and a 2.times.2 array of fluid ejector bodies wherein
the tray is effectively divided into four sections of 2.times.2
holders and the fluid ejector bodies are inserted in the enclosing
medium parts in each section. In this embodiment, the array of
fluid ejection cartridges 602 is mounted to dispensing bracket 688.
Fluid ejector actuators 650 (see FIG. 6a) are operably coupled to
fluid ejector bodies 620 and fluid controller 690 such that fluid
controller 690 activates fluid ejector actuators (see FIG. 6a) to
eject a fluid onto the interior surface of enclosing medium parts
606. In addition, fluid controller 690 is operably coupled to a
rotation mechanism (not shown) disposed on fluid ejection
cartridges 602 to rotate fluid ejector bodies 620 about a fluid
body longitudinal axis (not shown).
[0049] Transport mechanism 692 is coupled to either dispensing
bracket 688 or enclosing medium tray 684 or both depending on the
particular application in which dispensing system 604 is utilized.
Transport mechanism 692 is operably coupled to transport controller
694, and provides signals controlling movement of enclosing medium
tray 684 to align enclosing medium openings 608 to fluid ejector
bodies 620 as well as insert and withdraw fluid ejector bodies 620
from enclosing medium parts 606. For example, transport mechanism
692 may move enclosing medium tray 684 in X and Y lateral
directions while raising and lowering (i.e. movement in the Z
direction) dispensing bracket 688 to withdraw and insert fluid
ejector bodies 620 into enclosing medium parts 606 as shown in FIG.
6b. In alternate embodiments, other combinations of movements may
be utilized and controlled by transport mechanism 692 such as
rotation of enclosing medium tray 684 about a central axis to
provide additional alignment motion. In this embodiment, fluid
controller 690 and transport controller 694 may utilize any
combination of application specific integrated circuits (ASICs),
microprocessors and programmable logic controllers to control the
various functions of fluid dispensing system 604. The particular
devices utilized will depend on the particular application in which
fluid dispensing system 604 is utilized. In addition, dispensing
system 604 may optionally include an enclosing medium loader 698 to
load enclosing medium parts 606 into enclosing medium holders 686.
Further, dispensing system 604 may also include enclosing medium
rotator 685 to rotate enclosing medium parts 606 around an
enclosing medium longitudinal axis (see FIGS. 1a and 1b) thus
rotate the interior surface of the enclosing medium around the
fluid ejector body. Either rotation of enclosing medium parts 606
or rotation of fluid ejector bodies 620 or both can be utilized to
generate a two-dimensional array of discrete deposits dispensed
onto the interior surface of enclosing medium parts 606.
[0050] Optional inspection unit 696 may be utilized to provide
in-line, non-destructive quality assurance testing of the
manufactured articles. The particular function performed by
inspection unit 696 will depend on the particular application in
which dispensing system 604 is utilized. For example inspection
unit 696 may be utilized to monitor the quantity of material
deposited when dispensing bioactive agent on the interior surface
of a gelatin capsule. Another example would be monitoring a
reaction product when dispensing various reactants on the interior
surface of a vial or other suitable container. For example near
infrared or other optical techniques may be utilized to perform a
rapid in line assay of bioactive agent or agents on enclosing
medium parts 606. Further inspection unit 696 may also be utilized
to optically monitor the quality of characters generated on the
interior surface of a jar, vial or other suitable container.
[0051] Referring to FIG. 7 a flow diagram of a method of
manufacturing a fluid ejector head according to an embodiment of
the present invention is shown. Substrate creation process 780
includes making a substrate adapted to be inserted into an opening
of an enclosing medium. The substrate may be made from any ceramic,
metal, or plastic material capable of forming the appropriate size
to fit within the opening of the elongated enclosing. The
particular material utilized for the substrate depends on the
particular application in which the fluid ejector head will be
utilized. For example, if active devices are desirable then
substrates having the thermal, chemical, and mechanical properties
suitable for semiconductor processing, such as, various glasses,
aluminum oxide, polyimide substrates, silicon carbide, and gallium
arsenide, to name a few, may be utilized. However, if a "direct
drive" is desirable then substrates having less stringent thermal,
chemical and mechanical properties can be utilized, such as various
plastic materials. Substrate creation process 780 includes forming
the substrate in the desired shape, such as cylindrical,
rectangular, or other polygonal structures depending on the
particular application in which the fluid ejector head will be
utilized.
[0052] Optional active device forming process 782 utilizes
conventional semiconductor processing equipment to form
transistors, as well as other logic devices required for the
operation of the fluid ejector head, on the substrate. These
transistors and other logic devices typically are formed as a stack
of thin film layers on the substrate. The particular structure of
the transistors is not relevant to the invention, however, various
types of solid-state electronic devices may be utilized, such as,
metal oxide field effect transistors (MOSFET), or bipolar junction
transistors (BJT). As described earlier other substrate materials
may also be utilized. Accordingly the substrate materials may also
include any of the available semiconductor materials and
technologies, such as thin-film-transistor (TFT) technology using
polysilicon on glass substrates.
[0053] Fluid energy generating element creation process 784 depends
on the particular transducer being utilized in the fluid ejector
head to create the fluid ejector actuator. Typically, for thermal
resistor elements, a resistor is formed as a tantalum aluminum
alloy utilizing conventional semiconductor processing equipment,
such as sputter deposition systems for forming the resistor and
etching and photolithography systems for defining the location and
shape of the resistor layer. In alternate embodiments, resistor
alloys such as tungsten silicon nitride, or polysilicon may also be
utilized. In other alternative embodiments, fluid drop generators
other than thermal resistors, such as piezoelectric, or ultrasonic
may also be utilized. In still other embodiments, such as those
utilizing compressed air the fluid ejector actuator may be created
by forming one or more diaphragms in fluid communication with the
nozzles. In addition, in those embodiments utilizing active devices
formed on the substrate, some of the active devices are, typically,
electrically coupled to the fluid energy generating elements by
electrical traces formed from aluminum alloys such as aluminum
copper silicon commonly used in integrated circuit technology.
Other interconnect alloys may also be utilized such as gold, or
copper.
[0054] Chamber layer forming process 786, depends on the particular
material chosen to form the chamber layer, or the chamber orifice
layer when an integrated chamber layer and nozzle layer is used.
The particular material chosen will depend on parameters such as
the fluid being ejected, the expected lifetime of the fluid ejector
head, the dimensions of the fluid ejection chamber and fluidic feed
channels among others. Generally, conventional photoresist and
photolithography processing equipment or conventional circuit board
processing equipment is utilized. For example, the processes used
to form a photoimagable polyimide chamber layer would be spin
coating and soft baking. However, forming a chamber layer, from
what is generally referred to as a solder mask, would typically
utilize either a coating process or a lamination process to adhere
the material to the substrate. Other materials such as silicon
oxide or silicon nitride may also be utilized as a chamber layer,
using deposition tools such as plasma enhanced chemical vapor
deposition or sputtering.
[0055] Sidewall definition process 788 typically utilizes
photolithography tools for patterning. For example after either a
photoimagable polyimide or solder mask has been formed on the
substrate, the chamber layer would be exposed through a mask having
the desired chamber features. The chamber layer is then taken
through a develop process and typically a subsequent final bake
process after develop. Other embodiments, may also utilize a
technique similar to what is commonly referred to as a lost wax
process. In this process, typically a lost wax or sacrificial
material that can be removed, through, for example, solubility,
etching, heat, photochemical reaction, or other appropriate means,
is used to form the fluidic chamber and fluidic channel structures
as well as the orifice or bore. Typically, a polymeric material is
coated over these structures formed by the lost wax material. The
lost wax material is removed by one or a combination of the
above-mentioned processes leaving a fluidic chamber, fluidic
channel and orifice formed in the coated material.
[0056] Nozzle or orifice forming process 790 depends on the
particular material chosen to form the nozzle layer. The particular
material chosen will depend on parameters such as the fluid being
ejected, the expected lifetime of the printhead, the dimensions of
the bore, bore shape and bore wall structure among others.
Generally, laser ablation may be utilized; however, other
techniques such as punching, chemical milling, or micromolding may
also be used. The method used to attach the nozzle layer to the
chamber layer also depends on the particular materials chosen for
the nozzle layer and chamber layer. Generally, the nozzle layer is
attached or affixed to the chamber layer using either an adhesive
layer sandwiched between the chamber layer and nozzle layer, or by
laminating the nozzle layer to the chamber layer with or without an
adhesive layer.
[0057] As described above (see FIGS. 4-5) some embodiments will
utilize an integrated chamber and nozzle layer structure referred
to as a chamber orifice or chamber nozzle layer. This layer will
generally use some combination of the processes already described
depending on the particular material chosen for the integrated
layer. For example, in one embodiment a film typically used for the
nozzle layer may have both the nozzles and fluid ejection chamber
formed within the layer by such techniques as laser ablation or
chemical milling. Such a layer can then be secured to the substrate
using an adhesive. In an alternate embodiment a photoimagible epoxy
can be disposed on the substrate and then using conventional
photolithography techniques the chamber layer and nozzles may be
formed, for example, by multiple exposures before the developing
cycle. In still another embodiment, as described above the lost wax
process may also be utilized to form an integrated chamber layer
and nozzle layer structure.
[0058] Fluid inlet channel forming process 792 depends on the
particular material utilized for the substrate. For example to form
the fluid inlet channels in a silicon substrate a dry etch may be
used when vertical or orthogonal sidewalls are desired. However,
when sloping sidewalls are desired a wet etch such as tetra methyl
ammonium hydroxide (TMAH) may be utilized. In addition,
combinations of wet and dry etch may also be utilized when more
complex structures are utilized to form the fluid inlet channels.
Other processes such as laser ablation, reactive ion etching, ion
milling including focused ion beam patterning, may also be utilized
to form the fluid inlet channels depending on the particular
substrate material utilized. Micromolding, electroforming,
punching, or chemical milling are also examples of techniques that
may be utilized depending on the particular substrate material
utilized.
[0059] Fluid channel forming process 794, typically, will utilize
an injection molding process to form the desired shape of the fluid
channels depending on the particular application in which the fluid
ejector head will be utilized. The injection molded fluid channel
would then be mounted, using a suitable adhesive, to either the
substrate or a fluid body housing depending on the particular
structure being utilized.
[0060] Optional fluid body housing forming process 796, typically,
will utilize an injection molding process to form the desire shape
of the fluid body housing depending on the particular application
in which the fluid ejector head will be utilized. In some
embodiments, such as that shown in FIGS. 2a and 2b, fluid body
housing forming process 796 and fluid channel forming process 794
may be combined in a single process to form both the fluid body
housing and the fluid channels. For example, as shown in FIG. 2a
attachment of the fluid body housing to the substrate utilizing an
appropriate adhesive creates the fluid ejector body adapted to be
inserted into the opening of the enclosing medium. In still other
embodiments the fluid ejector body is created by the nozzle layer
formed on the chamber layer formed on the substrate as illustrated
in FIG. 3.
[0061] An exemplary embodiment of a method for using a fluid
dispensing system to dispense discrete deposits of material onto
the interior surface of an enclosing medium is shown as a flow
diagram in FIG. 8. Aligning enclosing medium process 810 is used to
align the opening in the enclosing medium to the fluid ejector head
so that the fluid ejector body may be inserted into the enclosing
medium. The enclosing medium is, typically, in an enclosing medium
tray or other holding device. The tray or other holding device is
under the control of a transport mechanism and the transport
controller. Any of the conventional techniques for aligning parts
may be utilized. For example, an electric or pneumatic motor or
other actuator may move the tray or other holding device in X and Y
lateral directions to establish proper alignment of the enclosing
medium to the fluid ejector head. In addition, typically a theta or
rotational alignment about a Z-axis will also be provided. Further,
sensors located on the holding device, or an optical vision system
or combination thereof will, typically, be utilized to provide feed
back that the enclosing medium is properly aligned to the fluid
ejector body. In alternate embodiments, the transport controller
may be linked to a fluid ejection cartridge or fluid ejector head,
mounted to a dispensing bracket, providing movement of the fluid
ejector body or both the fluid ejector body and the holding device
to properly align the enclosing medium to the fluid ejector
heads.
[0062] Inserting fluid ejector body process 820 is utilized to
insert the fluid ejector body into the opening of the enclosing
medium. The fluid ejector head is typically under the control of
fluid ejection cartridge or fluid ejector head position controller
or transport mechanism and transport controller. For example, in
one embodiment, an electric or pneumatic motor may raise and lower
in the Z direction the fluid ejector head providing the movement
for inserting the fluid ejector body into the opening of the
enclosing medium. In alternate embodiments, the tray, or other
holding device or a combination of the tray and the fluid ejector
head are moved to insert the fluid ejector head into the opening of
the enclosing medium.
[0063] Activating fluid ejector actuator process 830 is utilized to
eject the fluid from at least one nozzle disposed on the fluid
ejector body. Typically, a drop-firing controller or fluid
controller in the fluid dispensing system, coupled to the fluid
ejector head, activates the fluid ejector actuator, to eject drops
of the fluid. For those embodiments, utilizing a fluid energy
generating element, such as piezoelectric or thermal resistor
elements, the drop firing controller will, typically, activate a
plurality of fluid energy generating elements to eject essentially
a drop of the fluid each time a fluid energy generating element is
activated. Typically the fluid energy generating elements can
reproducibly and reliably eject drops in the range of from about
five femtoliters to about 10 nanoliters. Such a drop size
corresponds to deposits in the picogram to microgram range
depending on the ratio of the amount of the desired material to be
deposited to the amount of solvent in the fluid drop ejected.
However, depending on the particular application in which the fluid
dispensing system is utilized, the size of these fluid drops can be
controlled, in the range from about 5 femtoliters to about 1
microliter. Such a drop size corresponds to deposits in the
picogram to milligram range depending on the ratio of the amount of
the desired material to be deposited to the amount of solvent in
the fluid drop ejected.
[0064] Dispensing fluid process 840 is utilized to dispense and
control the location of the ejected fluid drops on the inside
surface of the enclosing medium to form the discrete agent
deposits. Depending on the particular fluid ejector head utilized,
the fluid drops may be ejected through the nozzles along a nozzle
ejection axis, at a predetermined ejection angle from a fluid body
normal. In one embodiment, the nozzle ejection axis is aligned at
an angle between about 0.degree. and about 60.degree. from the
fluid body normal. In alternate embodiments, a fluid ejector head
having a nozzle ejection axis aligned at an angle between about
0.degree. and about 45.degree. from the fluid body normal may be
utilized. Preferably, a fluid ejector head with a nozzle ejection
axis substantially perpendicular to a fluid ejector body
longitudinal axis is utilized.,
[0065] In addition, depending on the particular fluid ejector body
utilized dispensing fluid process 840 may also include an optional
rotational displacement process. The rotational displacement
process is utilized, for example, to create rows of the discrete
deposits for those embodiments utilizing fluid ejector heads having
a single column of nozzles for a particular fluid. By utilizing
rotation, dispensing fluid process 840 may generate a
two-dimensional array forming an areal density of fluid deposits on
the interior surface of the enclosing medium. Three-dimensional
arrays may also be generated by dispensing fluid deposits on top of
previously dispensed fluid deposits. In addition, for those
embodiments utilizing fluid ejector heads having multiple columns
of nozzles the rotational displacement may be utilized to form rows
of the discrete deposits having a smaller spacing between deposits
than obtained with the same fluid ejector head without rotation.
The rotational displacement may be accomplished by any of the
conventional techniques utilized for rotation such as electrical or
pneumatic motors, or piezoelectric motors to name just a couple of
examples. The rotational displacement may be imparted to the
enclosing medium, to the fluid ejector body, or some combination
thereof.
[0066] Dispensing fluid process 840 may also include an optional
vertical displace process. The vertical displacement process may be
utilized to create columns of the discrete deposits having a
smaller spacing between deposits than normally obtained with the
same fluid ejector head without vertical displacement. The fluid
drop controller typically controls the vertical displacement,
however a separate controller may also be utilized. For example,
the fluid drop controller may be coupled to the tray position
controller or the fluid ejector head controller or both to generate
the appropriate vertical displacement. In alternate embodiments,
separate controllers and motors or other actuators may be utilized
to generate the appropriate vertical displacement. By utilizing
various combinations of rotation and vertical displacement various
structures may be generated, from simple two-dimensional arrays, or
overlapping deposits forming a layer, to more complex structures
such as three-dimensional arrays.
[0067] Referring to FIG. 9a an article of manufacture made using a
fluid dispensing system according to an embodiment of the present
invention is shown in a perspective view. In this embodiment,
enclosing medium 906 is container 930 that has interior surface 910
upon which is printed various alphanumeric characters 950
representing information in a human-perceptible form and bar code
940 representing information in a machine under stood form.
Although the information depicted in FIG. 9a is what is commonly
referred to as a "consumer coupon" alternate embodiments, may
include any desirable consumer or manufacturing information. In
addition the information can be any symbol, icon, image, or text or
combinations thereof, such as a company logo or cartoon character.
Other examples of various forms in which the information may be
presented are a one-dimensional bar code, a text message, a code,
or hologram.
[0068] Referring to FIG. 9b an article of manufacture having a more
variable shape may also be made using a fluid dispensing system
according to an embodiment of the present invention is shown in a
perspective view. In this embodiment, enclosing medium 906 is
flexible package 932 that has interior surface 910 upon which is
printed, in reverse letters to be legible from the outside, various
alphanumeric characters 952. Alphanumeric characters 952 are
generated using ink deposits or dots (not shown) that are deposited
on interior surface 910 of flexible package 932 in patterns using
dot matrix manipulation or other means. As described above in for
FIG. 9a an image, alphanumeric characters, or a machine understood
code such as a one or two-dimensional bar code may be utilized.
[0069] Referring to FIG. 9c a label made on a gelatin capsule using
a fluid dispensing system according to an embodiment of the present
invention is shown in a perspective view. In this embodiment,
enclosing medium 906 is gelatin capsule 934 that has interior
surface 910 upon which is printed, pattern 954 using dot matrix
manipulation or other means to generate an image, alphanumeric
characters, or a machine understood code. In this embodiment the
pattern 954 utilizes discrete ink deposits (not shown) to generate
the alphanumeric characters "agh3" printed on the inside of
enclosing medium 906 in reverse letters to be legible from the
outside. By printing on the inside of enclosing medium 906, such
characters or images are not as easily rubbed off or washed off as
for conventional packages printed either on the outside surface or
on labels subsequently applied to the outer surface of the
package.
* * * * *