rexresearch.com
Ayyoub MOMEN, et
al.
Ultrasonic Dryer
Related :
FORD : http://www.rexresearch.com/ford/fordryer.htm
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-- Ultrasonic Washer
https://www.ornl.gov/content/novel-ultra-low-energy-consumption-ultrasonic-clothes-dryer
Novel Ultra Low-Energy Consumption
Ultrasonic Clothes Dryer
The development of the ultrasonic clothes dryer at Oak Ridge
National Laboratory is a prime example of collaboration among
various divisions at the lab — drawing upon the expertise
necessary no matter where a scientist sits to transform a
well-researched idea into a great invention.
When researchers in the Energy and Transportation Science Division
(ETSD) decided to turn the experiments they had been conducting —
on the use of ultrasonic transducers to nebulize water—into a
demonstration of how the technology could be applied to drying
clothes, their mechanical engineering background was key to
achieving success.
The process involves piezoelectric transducers placed in direct
contact with wet fabric, generating high frequency vibrations that
atomize water, turning it into a mist. Taking thermal heat out of
the drying process could result in significant energy savings
compared with conventional clothes dryers that rely on heated air.
But scaling the project up from an experiment on a tiny square of
fabric to a demonstration of a full-size press-style dryer
required more sophisticated electronics and controls.
That’s when the Electrical and Electronics Systems Research (EESR)
Division answered ESTD’s call for assistance. Both organizations
are part of the Energy and Environmental Sciences Directorate.
After examining the setup by principal investigator Ayyoub Momen
and researcher Viral Patel in ETSD’s Building Equipment Research
Group, the electrical engineers and other researchers in EESR’s
Sensors and Embedded Systems (SES) Group assisted with the
electronics and some of the physics aspects of the transducers.
They designed and built a series of amplifiers and electronic
drivers as the researchers tested various frequencies, wave
shapes, amplitudes, and voltage levels to help determine the best
kind of piezoelectric transducers to use in the demonstration.
EESR also had students available who were able to work on the
project — with guidance — on such tasks as drawing up schematics
and producing needed equipment, noted Roger Kisner, who led the
SES group effort. Participating were Christi Johnson, a staff
member currently working on an MS in Electrical Engineering;
Frederick Kyle Reed, pursuing a PhD in Electrical Engineering; and
Evan Schlenker, who holds a BS in Electrical Engineering and who
will begin pursuing a degree in the same area in the fall of 2016.
Later, SES called on Reed’s services to develop, simulate, mount,
and test circuits.
Momen said that about 80% of the work on the prototype dryer was
performed in Kisner’s lab space.
“From the first day, the SES group was very impactful on the
project,” Momen said, adding that SES identified the correct
commercial amplifier for the prototype and later designed and
built three custom amplifiers that significantly boosted the
efficiency of the demonstration.
“That’s what we do in this group: We get so involved that
sometimes you can’t distinguish us,” Kisner said. “We want these
projects to succeed. And so we’re not just a support technician
who comes in; we become a researcher with the original team and
drive the work forward.”
“We tend to have a very wide background in our group, with
expertise in electronics, electrical systems, optics, whatever
needs to be brought to bear,” Kisner said. “We tend to do a lot of
rapid prototyping of things.
“Someone might come to us and say, ‘I’m building a new
whatever-it-is, and no one’s ever done this before. Can you
quickly put together something that would achieve the following
things?’ And then we might respond, ‘Oh, I’ve never heard of it.
Let’s do it.’ And then we step out and do what it takes to make it
work,” said Kisner, who is a Distinguished R&D Staffer and
Distinguished Inventor at ORNL.
Next up for the dryer project is studying the feasibility of
moving to a drum-type application typical in residential dryers.
One challenge to that scale-up is the requirement that the clothes
and the transducers come in contact with each other. Momen said
coupling can be accomplished through several means, from relying
on the weight of the clothes to adding a bit more centrifugal
force or backing reinforcement.
The energy savings potential is enormous because conventional
clothes dryers using thermal heat currently consume about 1% of
the energy used in the United States, Momen noted.
Using an ultrasonic process instead could cut drying time in half
and use perhaps one-tenth of the power, with resulting savings in
energy, cost, and time, Kisner said.
The invention can be scaled up to industrial applications, with
the potential for collaboration with the pulp and paper industry
for use in drying tons of pulp at a time or with carpet
manufacturers in fiber drying, the researchers said.
https://energy.gov/eere/buildings/downloads/novel-ultra-low-energy-consumption-ultrasonic-clothes-dryer
Building Energy Efficiency Frontiers and Incubator
Technologies (BENEFIT) - 2014 (FOA DE-FOA-0001027) Project
Objective
DOE’s Building Technologies Office is seeking new clothes dryer
technologies that can increase the energy factor (EF) from 3.7 to
5.43 lb/kWh without increasing drying time by more than 20% over
baseline units. The goal of this project is to develop a clothes
dryer prototype, using ultrasonic transducers, with an EF above 10
lb/kWh. Drying time is predicted to be ~20 minutes. This project
aims to make the process of drying clothes very energy efficient.
Parting from conventional heat-based drying methods, the technique
used here relies on using piezoelectric transducers to generate
high frequency mechanical vibration to mechanically extract
moisture from the fabric as cold mist.
PROJECT IMPACT
This project can potentially revolutionize the clothes dryer
industry. Being able to remove impurities in the water contained
in clothes might lead to softer and higher-quality dried clothes,
which is good for marketability of the final product. Eliminating
the need for a high flow rate, high temperature air will minimize
issues with lint in the air processing system. At the end of the
project, appliance manufacturers including GEA will be ready to
invest in this technology and commercialize it. This will result
in the U.S. becoming the leader in the clothes drying industry and
generate new jobs and innovative applications of the technology.
This technology also has the potential for 0.4 quads of energy
savings.
https://www.youtube.com/watch?v=PjSjpVYpg0c
https://www.youtube.com/watch?v=poVwCmqcue8
Ultrasonic clothes dryer demonstration
Oak Ridge National Laboratory
Oak Ridge National Laboratory researcher Ayyoub Momen demonstrates
a direct contact ultrasonic clothes dryer under development by
ORNL in collaboration with General Electric (GE) Appliances. This
novel approach uses high-frequency mechanical vibrations instead
of heat to extract moisture as cold mist, dramatically reducing
drying time and energy use. Funding for this project was
competitively awarded by DOE’s Building Technologies Office in
2014. For more information please contact momena@ornl.gov.
WO2016182832
DRYER USING HIGH FREQUENCY VIBRATION
Inventor: MOMEN AYYOUB, et al.
A dryer includes a plurality of piezoelectric transducers 100 in
electrical communication with a high frequency piezoelectric
oscillation generator. The piezoelectric oscillation generator
controls the duty cycle and resonant frequency source signal that
drive the plurality of piezoelectric transducers 100
non-continuously. The piezoelectric transducers 100 dry the wet
articles without heating air passing through the articles.
BACKGROUND
1. Priority Claim.
[001] This application claims priority to U.S. Provisional Patent
Application No. 62/158,562, filed May 8, 2015, titled "Clothes
Dryer Using Ultrasound Phenomena", which is herein incorporated by
reference.
2. Statement Regarding Federally Sponsored Research and
Development.
[002] This invention was made with United States government
support under Contract No. DE-AC05-00OR22725 awarded by the United
States Department of Energy. The United States government has
certain rights in the invention.
3. Technical Field.
[003] This disclosure relates to high frequency drying and more
specifically to systems and processes that improve drying
efficiency.
4. Related Art.
[004] Conventional clothes dryers use an energy source such as
natural gas or electricity to dry clothes. A gas or electric
heater heats air that passes through the clothes as they tumble
and turn. Moisture is removed from the clothes via the heated air
by converting the water retained in the clothes into vapor, which
requires a substantial amount of continuous energy. The heat that
dries the clothes is then removed and exhausted from the dryer.
[005] Besides the inefficiency and the cost of converting cold air
into hot air, water into vapor, and venting hot wet air,
conventional clothes dryers also pose safety hazards. When the
temperature exceeds a safe operating threshold, the dryers can
overheat, damaging the clothes, the dryer, and the structures near
them. Such failures can occur when airflow is restricted or when a
dryer's thermal cutoff switch fails. There is a need for a system
and process that provides a more efficient, less expensive, and a
safer process to dry clothes. A technical challenge addressed by
this disclosure is that of improving the efficiency of the drying
process so that it may be used safely in vented and ventless
systems. BRIEF
DESCRIPTION OF THE DRAWINGS
[006] Figure 1 is a dryer with mist collectors that overlie
piezoelectric mesh transducers.
[007] Figure 2 is a close up view of the mist collectors
overlaid on piezoelectric mesh transducers, and the collector
channels of Figure 1.
[008] Figure 3 shows the schematic of the original power
signal, the modulation signal, and the resultant power supplied
to the piezoelectric mesh transducers.
[009] Figure 4 is a close up view of the collector
channels.
[010] Figure 5 shows the original power signal, the
modulation signal, and the resultant power supplied to the high
frequency mesh transducers.
[011] Figure 6 shows a slip ring power connection to a
rotary tumbler drum.
[012] Figure 7 shows a bipolar burst modulation.
[013] Figure 8 is a block diagram of a customized
modulation.
[014] Figure 9 shows piezoelectric mesh transducer drivers.
[015] Figure 10 is a sandwich press/iron dryer/ironing
machine.
[016] Figure 11 is wringer high frequency dryer.
[017] Figure 12 is a multi-stack of transducers that apply
simultaneous variable frequencies to an article.
[018] Figure 13 is an exemplary method of drying a wet
article.
[019] Figure 14 shows portions of the means to remove
nebulized water droplets from a wet article.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[020] The disclosed high frequency technology is clean, efficient,
and environmentally friendly. The collection of systems and
processes disclosed are herein referred to as "the systems". The
systems may be adapted to existing dryers including blower and
lint filter dryers, drum shroud dryers, and integrated drum shroud
dryers. The systems may also be adapted to new innovative dryer
designs including wringer type dryers and sandwich press/iron
dryers. The innovation overcomes technical problems in the
clothing industry, paper industry, food industry, mining industry,
environmental industry, and in chemical manufacture, to name a
few. It is used in stand-alone systems and large-scale enterprise
systems. The systems' high frequency mesh transducers convert
electrical signals into high frequency mechanical waves. They also
convert ultrasound and mechanical waves into electrical signals
when not powered by electrical signals. The technology makes use
of high frequency transceivers that both (a) sense pressure and
high frequency signals and (b) transmit pressure and high
frequency signals. High frequency signals include ultrasonic
signals that generate waves having a frequency above twenty
thousand cycles per second.
[021] One or more high frequency generators (also known as a high
frequency controller, controller, amplifier, driving power driver,
or drive controller) control the duty cycle and resonant
frequencies that drive the high frequency transducers/transceivers
(herein referred to as high frequency piezoelectric transducers).
A drying effect is achieved by vibrating an article through
piezoelectric and substrate elements and one, two, or three or
more separate meshes within about a 100 Hz to 400 kHz range with a
preferable irradiation frequency of about 130 kHz. Other
frequencies for irradiation are also possible including about 50
kHz to about 90 kHz, about 100 kHz to about 1 MHz and about 500
kHz to about 2 MHz. The separate spaced apart meshes comprise a
plurality of distinct mechanically actuated grids formed by the
intersection of wires, polyester lines, or nylon lines, (or a
combination) for example; where each mesh is flexible and capable
of independent movement. The high frequency
transducers/transceivers are driven at a duty cycle within a range
of substantially 1% to substantially 30% or more. The transducer
duty cycle may be varied throughout the clothes drying cycle
process as a function of moisture level. Higher duty cycles are
possible including about 40% or about 50%, and up to about 90%
approaching 100%. During a drying process, capillary waves form on
the surface of liquid retained in an article. The wavelength of
the capillary waves depends on the irradiation frequency of the
high frequency transducers/transceivers. When oscillated with
sufficient intensity (amplitude), the water pinches off into
droplets that pass through the spaced apart meshes that partially
overlay an open inner annular area bounded by the piezoelectric
and substrate elements and passes through a cylindrical shroud
outlet. The water then passes through collector channels that
terminate at a reservoir or a drain. Unlike conventional dryers
that rely on heat energy to evaporate fluid retained by an article
into vapor, the disclosed high frequency transducers use
mechanical energy and vibrational energy. The term article in this
disclosure refers to the object being dried such as a fabric.
[022] Figure 1 and 2 illustrate dryers. The dryers have a
substantially rectangular shape and have a top 102, a bottom 104,
a front (not shown), a rear (not shown), and two opposing sides
106. The dryers include a substantially hollow rotary tumbler drum
108 wherein a user places articles such as clothes prior to
activating the dryer. The dryer may be in electrical communication
with an optional dryer timer (not shown). The timer is activated
upon activation of the dryer.
[023] In Figures 1 and 2 a plurality of mist collectors overlies
piezoelectric high frequency mesh transducers 100 (one
piezoelectric high frequency mesh transducer is labeled in Figure
1) in the hollow rotary tumbler drum 108. In some systems, mist
collectors are not used. Instead, only the piezoelectric high
frequency mesh transducers 100 (hereinafter referred to as high
frequency mesh transducers 100) are used and like the mist
collectors they are a unitary portion of a rotary tumbler drum
108. In Figure 1 and 2, the concave surfaces of the high frequency
mesh transducers 100 come in contact with the articles as the
articles tumble within the rotary tumbler drum 108. When contact
occurs some high frequency mesh transducers 100 alert an high
frequency generator by generating and transmitting a voltage
proportional to the force that is applied by the articles to the
high frequency mesh transducers 100 (a.k.a. the feedback signal).
Once the feedback signal is detected at the high frequency
generator via an electrical/data bus or monitoring line, the high
frequency generator powers up the high frequency mesh transducers
100 that transmitted the alert which cause the transducers' mesh
surfaces to vibrate at a resonant frequency. The vibration causes
the radial outward ejection of liquid droplets from the article
through the high frequency mesh transducers 100 through the open
inner annular area bounded by the piezoelectric and substrate
elements. The curved shape of the high frequency mesh transducer
surfaces cause the irradiated liquid to coalesce in the annular
space and flow downward through the piezoelectric and substrate
elements into the collector channels 110 through the aide of
gravity, and when the hollow rotary tumbler drum 108 is rotating,
through centrifugal force induced by rotation. The liquid that
passes through the high frequency mesh transducers 100 are
collected in a reservoir or pass through to a drain. In these
systems, the drying process occurs only when there is direct
contact between one or more articles and the high frequency mesh
transducers 100. [024] In some alternative systems the duty cycles
of the actuated high frequency mesh transducers 100 are determined
by the rotational rate of the hollow rotary tumbler drum 108 and
the proportional feedback signal generated by the force that is
applied by the articles against the high frequency mesh
transducers 100. In these alternative systems, as the articles dry
the weight of the articles and the proportional feedback voltage
signals generated by the high frequency mesh transducers 100
decrease. In turn, this causes the burst-width modulated signal
delivered by the high frequency generators to increase. Notably,
the power consumed by some high frequency systems is inversely
related to the level of moisture retained in the articles or the
article's weight and may be used to calibrate the high frequency
generator when the articles are first loaded within the rotary
tumbler drum 108. In operation, when articles are initially
loaded, high frequency generators drive the high frequency mesh
transducers 100 at their resonant operating efficiency based on
the detected moisture or weight. As the articles eject the liquid
or a predetermined amount of the liquid, some high frequency
generators proportionally increase the power sourced to the high
frequency mesh transducers 100 by increasing the duty cycle
sourcing the high frequency mesh transducers 100 as shown in
Figure 3 until the feedback signal falls or fades below a
predetermined threshold that is determined from empirical
evidence. When the level of the feedback signal falls below the
threshold, the high frequency generator shuts off the high
frequency mesh transducers 100 completely and in some systems the
rotation of the hollow rotary tumbler drum 108 and/or dryer. The
system shut down may prevent the over drying of articles, which
causes the majority of damage to fabric coming out of conventional
dryers. Some or all of the systems may draw in or inject hot air
into the hollow rotary tumbler drum 108 to complete the drying
process or when the drying period ends to provide warm articles
before the dryer shuts down. When fabric is cooler coming out of a
dryer, some users incorrectly assume that the articles are still
wet and require more drying even when most of the moisture that
was in the fabric had been extracted. The addition of hot air at
the end of the drying cycle merely enhances the operator
experience of unloading the articles from the dryer.
[025] While each of the systems described in this disclosure are
shown in vent-less systems, other systems incorporate the high
frequency technology in vented systems. For example, when
retrofitted to a conventional blower lint filter dryer, the high
frequency systems may alternatively or additionally couple a lint
filter that overlies an array of high frequency transducers or
high frequency mesh transducers 100 that include a series of
meshes serially aligned, stacked, and spaced apart in an array.
When the liquid droplet sizes in the irradiated mist are of
appropriate size, they are entrained in the airflow and
transported out of the hollow rotary tumbler drum 108 through the
lint filter and other meshes serially stacked and aligned that
make up part of the high frequency mesh transducers 100. The
liquid droplets coalesce into larger droplets that are then
collected in collector channel 110 that terminates at a reservoir
or passes to a drain and the dehumidified airflow is exhausted
through a vent. In Figures 1, 2 and 4 the collector channel 110 is
annular shaped and concentric with a portion of the hollow rotary
tumbler drum 108 and terminates in a reservoir shown as a
collector. In this system the lint filter is multi-functional
element as it catches the dust and lint discarded from the article
during the drying process and further dehumidifies substantially
all of the moisture ejected from the article suspended in the air.
Further, the connection between the lint filter and the high
frequency mesh transducers 100 is not limited to a mechanical or
physical coupling; rather it is a connection that may include
intervening parts to the extent they do not substantially impeded
air flow intended to pass through the lint filter and high
frequency mesh transducers 100 and a vent during operation of the
dryer.
[026] While the number of meshes, opening size, and materials used
to manufacture the meshes used in the high frequency mesh
transducers 100 depend on the application and the type of liquid
being extracted from an article, polyester mesh with opening size
of about 0.84 x 0.84 mm are effective when operating in
environmental conditions common to consumer clothes dryers. The
opening size of the mesh is similar to that of a lint filter and
the optimum number of spaced apart, directly adjoining meshes
stacked in series (overlying each other above the piezoelectric
and substrate elements spaced apart by only by a flat ring made of
metal or plastic such as O-rings) is three, which results in a
moisture collection efficiency of about 50%. As additional meshes
are added in series the cumulative airflow pressure drops along
with the moisture collection efficiency.
[027] Because drying occurs when direct contact occurs between an
article and one of the mesh layers of the high frequency mesh
transducers 100, the high frequency mesh transducers 100 are not
activated or powered-up continuously resulting in an energy
consumption that is between two to five times less than the energy
consumed by conventional dryers. In operation, when the high
frequency mesh transducers 100 are activated, the high frequency
mesh transducers 100 push the article upward away from the high
frequency mesh transducers 100. When contact is lost, power is not
sourced to the high frequency mesh transducers 100, meaning that
the power is delivered only in bursts when contact occurs between
the article and the high frequency mesh transducers 100. After a
finite amount of time, the article falls back into contact with
the high frequency mesh transducers 100 due to gravity, and in
some cases centrifugal force. While direct contract with the high
frequency mesh transducers 100 reoccurs, detection occurs when the
articles mechanically stress the high frequency mesh transducers
100. In other systems passive sensors such as passive infrared
sensors detect direct contact between the articles and the high
frequency mesh transducers 100. The term passive in this instance
refers to the fact that sensors do not generate or radiate any
energy during the detection process.
[028] The energy consumed per unit mass of water is calculated as:
Energy per Unit of Mass = Drying Time x Duty Cycle x Rated Power
of Transducer
Mass of Water
When applying different duty cycles and frequencies, exemplary
high frequency mesh transducers 100 which typically operate at
resonance frequency of 130 kHz and modulated by modulation
frequency of about 600 Hz at about a 60% duty cycle. The minimum
energy consumption per unit mass of water is about 0.198 kWh/kg,
which is about half the energy consumed when the high frequency
mesh transducers 100 were powered up continuously. This is about
115thof the energy that is used in the conventional electric
dryers.
[029] As shown in Figure 5, high frequency generators supply power
to the high frequency mesh transducers 100 through a binary
modulated signal. Power is supplied only when the modulating
signal is active (high). The resulting mixing of the power wave
and the modulated signal renders the power supplied to the high
frequency mesh transducers 100. As explained, in some alternative
systems the modulation signal may vary with the rate of rotation
of the hollow rotary tumbler drum 108 when the hollow rotary
tumbler drum 108 is used and contact is detected between an
article and one or more high frequency mesh transducers 100. In
other alternative systems the duty cycle of the modulation signal
varies with the amount of mechanical stress that occurs in the
high frequency mesh transducers 100 that may be detected by the
proportional voltage generated by the high frequency mesh
transducers 100 that is monitored by the high frequency
generators.
[030] To deliver power, the driver and power distribution
architecture may use a slip- ring, a rotary electrical joint, a
collector or an electric swivel. The slip ring keeps continuous
connections with the high frequency mesh transducers 100 that are
part of the hollow rotary tumbler drum 108 as shown in Figure 6.
The power delivered through the slip ring sources individual high
frequency mesh transducer drivers. The individual high frequency
mesh transducer drivers provide substantially uniform operation
despite the distinctive operating responses of each of high
frequency mesh transducers 100. The resonant frequency spread of
the high frequency mesh transducers 100 are minimized by this
individualized automated control. Due to the reduction in water
content during the drying process and differing fabric densities
in a single load, a wide variation of loading across a population
of high frequency mesh transducers 100 can cause radical shifts in
the high frequency mesh transducer 100 resonance that is
compensated by the individual or pairwise control via the power
distribution architecture. The system compensates for a wide and
variable spectrum of resonant frequencies at any moment during the
drying process via the driver and power distribution architecture
that makes up the high frequency generators by monitoring the
feedback of the high frequency mesh transducers 100 at the high
frequency generator. Each driver-transducer pair is substantially
driven to the high frequency mesh transducer 100 resonance (100 Hz
to 400 kHz, preferably 130 kHz) even under load that may render
the form of the modulation shown in Figure 5 and bursts shown in
Figure 7. This means that power delivery to the high frequency
mesh transducers 100 is not uniform but varies with the tolerances
of each of the high frequency mesh transducers 100 and the current
drying conditions.
[031] Figures 8 and 9 show the high frequency generator
functionality and the modulated amplification of the signal
sourcing the high frequency mesh transducers 100. In Figure 8, the
resonant frequency oscillator is automatically adjusted to the
resonant frequency during the drying process by one or more
controllers, one or more microprocessors (CPUs), one or more
signal processors (SPU), and one or more graphics processors
(GPUs), monitoring the output of the high frequency mesh
transducers 100. The resonant frequency oscillator generates a
square wave that is modulated by the modulation adjustment signal.
The mixing of the square wave and modulation signal (e.g.,
multiplier) generates a burst output that drives the high
frequency mesh transducers 100 at the resting and active state.
When bipolar drivers drive the high frequency mesh transducers
100, the bipolar output is amplified via an amplifier to the
operating voltage of the high frequency mesh transducers 100. In
some circuits a variable transformer is used to adjust the DC
power rail of the desired peak output voltage.
[032] Figure 10 shows the high frequency system within a sandwich
press/iron. The high frequency mesh transducers 100 are a unitary
part of the base of the press. The base is the structure that
supports the other elements of the sandwich press/iron is
supported and mounted. In use, as wet article such as a fabric is
placed on the upper most surface of the base such that it overlies
the high frequency mesh transducers 100. A lid composed of both
rigid and compressive material conforms to the irregular shape of
the article. In some systems a heating element is integrated into
the lower surface of the top lid to warm the article after the
drying process ends. As the lid is closed, the high frequency mesh
transducers 100 are activated; moisture is radially ejected
through the high frequency mesh transducers 100 toward the bottom
of the sandwich press/iron in response to the control of the high
frequency generator.
[033] Figure 11 shows a wringer high frequency dryer. The high
frequency dryer includes two rotating tumblers, which have high
frequency mesh transducers 100 (two are labeled) integrated within
them. As the wet fabric is passed through the gap between the
tumblers, it comes into contact with the high frequency mesh
transducers 100 and moisture is removed. The tumblers are
multifunctional as they hold articles such as clothes and further
mechanically extract water by feeding articles between the top
rotary tumbler and the bottom rotary tumbler. The top and bottom
rotary tumblers roll smoothly when the rotary tumblers are
manually or automatically driven. When the rotary tumblers are
engaged (rotating), the high frequency mesh transducers 100 in
contact with the article are activated; moisture is then ejected
radially inward in response to the control of the high frequency
generator. In some examples two or more pairs of rotating tumblers
are arranged in series.
[034] Figure 13 shows a method for drying a wet article. The
method may be, for example, implemented using any of the systems
described with respect to Figures 1 - 12. The systems may provide
two or more piezoelectric (high frequency mesh) transducers 100
having one or more resonant frequencies that are driven by one or
more amplifiers or one or more high frequency generators at 1302.
The method detects and selects the piezoelectric transducers in
contact with the article at 1304; sources an electric signal that
drives selected piezoelectric transducers to dry the wet
article(s) without circulating heated air at 1306; and resonates
the selected piezoelectric (high frequency mesh) transducers
non-continuously at their respective resonant frequencies only
when the selected piezoelectric (high frequency mesh) transducers
are in direct contact with the wet article at 1308. Alternatively,
or optionally, the method also injects hot air into the enclosure
drying the wet articles after the wet article is substantially dry
at optional 1310.
[035] While each of the disclosed high frequency technology
described may stand alone they also may be encompassed within
other systems and applications. Other alternate systems may
include any combinations of structure and functions described
above or shown in one or more or each of the figures. These
systems or methods are formed from any combination of structure
and function described. The structures and functions may process
additional or different high frequency mesh transducers 100 and
may be supported by other drying structures than a hollow rotary
tumbler drum 108, for example. Other high frequency mesh
transducers 100 that may be used for example, may apply several
widely different frequency signals to one or more articles to
affect the drying process include those that have separately tuned
piezoelectric and substrate mediums aligned in a stack as shown in
Figure 12. Different frequency ranges will vary the effects on the
drying process. A high-frequency signal will cause cavitation and
nebulization of the water entrained in an article such as a
fabric. A lower mid frequency signal (relative to the
high-frequency signal) acts to drive clusters of water away from
the article. An even relative lower frequency signal (relative to
the mid-frequency signal) can act to move one section of fabric
away from a transducer so that another wetter fabric section can
come in contact with the high frequency mesh transducers 100
stack.
[036] Other systems include variations of the spaced apart meshes
that comprise a plurality of distinct mechanically actuated grids
having penetrations that allow various types and viscosities of
liquids to pass there through. Some, all, or combinations of the
perforated meshes shown in Figure 14 are stacked in the high
frequency mesh transducers 100 as described above. The spaced
apart holes, slots, random perforations, and radial slots with
perforated and/or solid reinforcement bars and all combinations
thereof are preferred because various meshes and combinations draw
water from various articles more effectively and efficiently than
others. The combinations and piezoelectric elements provide means
to remove nebulized water droplets from a working side of an
article. A working side is the side of the article in direct
contact with one of the meshes of a high frequency mesh transducer
100. When part of the mesh transducer is in contact with a wet
article, a nebulized liquid flow path is established for
continuous liquid removal. When solid transducers are used in
other alternative systems a flow path is provided to channel
nebulized liquid droplets away from the articles.
[037] In each of the systems described meshes are excited by the
piezoelectric-medium fixed to a substrate. When powered, the
contraction and expansion of the piezoelectric- medium subjects
the substrate into bending vibrations. The bending of the
substrate excites the mesh vibrations substantially perpendicular
to the piezoelectric-medium vibrations. In these systems, the
piezoelectric medium and substrate is optimized to a vibration
frequency of about 100 Hz to about 400 kHz, preferably 130 kHz and
its shape is matched to the deflection shape of the substrate. To
ensure the irradiation fluid passes through the high frequency
mesh transducers 100, the piezoelectric medium may comprise a
piezoelectric-actuator annulus and the substrate may comprise an
annulus concentric with the piezoelectric-actuator and coupled at
least one mesh along an inner radial portion of the substrate. The
meshes are separated preferably by about a one-eighth of an inch
open annual O-ring on the upper and lower mesh surface. The mesh
surfaces are positioned with the piezoelectric-actuator annulus
and the substrate annulus within a hollow right circular cylinder
shroud.
[038] All or parts of the high frequency generator may include or
be controller by one or more controllers, one or more
microprocessors (CPUs), one or more signal processors (SPU), one
or more graphics processors (GPUs), one or more application
specific integrated circuit (ASIC), one or more programmable media
or any and all combinations of such hardware including ultrasonic
generators, ultrasonic controllers, ultrasonic microprocessors,
ultrasonic SPUs, ultrasonic GPUs, ultrasonic ASICs, etc. All or
part of the logic, specialized processes, and systems may be
implemented as instructions for execution by multi-core processors
(e.g., CPUs, SPUs, and/or GPUs), controller, or other processing
device and stored in a tangible or non-transitory machine-readable
or computer-readable medium such as flash memory, random access
memory (RAM) or read only memory (ROM), erasable programmable read
only memory (EPROM) or other machine-readable medium such as a
compact disc read only memory (CDROM), or magnetic or optical
disk. Thus, a product, such as a computer program product, may
include a storage medium and computer readable instructions stored
on the medium, which when executed in an endpoint, computer
system, or other device, cause the device to perform operations
according to any of the process descriptions or hardware
descriptions above.
[039] The term "coupled" disclosed in this description may
encompass both direct and indirect coupling. Thus, first and
second parts are said to be coupled together when they directly
contact one another, as well as when the first part couples to an
intermediate part which couples either directly or via one or more
additional intermediate parts to the second part. The term
"substantially" or "about" encompass a range that is largely
(ninety five percent or more), but not necessarily wholly, that
which is specified. It encompasses all but a significant amount.
When devices are responsive to or occur in response to commands
events, and/or requests, the actions and/or steps of the devices,
such as the operations that devices are performing, necessarily
occur as a direct or indirect result of the preceding commands,
events, actions, and/or requests. In other words, the operations
occur as a result of the preceding operations. A device that is
responsive to another requires more than an action (i.e., the
device's response to) merely follow another action.
[040] While various embodiments of the invention have been
described, it will be apparent to those of ordinary skill in the
art that many more embodiments and implementations are possible
within the scope of the invention. Accordingly, the invention is
not to be restricted except in light of the attached claims and
their equivalents.