Note: Descriptions are shown in the official language in which they were submitted.
CA 02723652 2010-12-01
WATER-POWERED HAND-WASHING SYSTEM AND METHOD
FIELD OF THE INVENTION
[0001] The present invention generally relates to the field of personal
hygiene. In particular, the
present invention is directed to a water-powered hand-washing system and
method.
BACKGROUND
[0002] All human surfaces harbor bacteria. Normal skin has a balance of
nonpathogenic
bacteria in its deeper layers (resident flora) and a transient population of
bacteria in its superficial
layers that can cause disease. By virtue of their role in touching public
items, processing food,
picking noses, satisfying itches and handling the paper-chores, the hands
provide the greatest sample
and volume of bacteria from the daily environment. If those digits carry
pathogenic E. coli,
Samonella, methicillin resistant Staph aureus, Clostridia dificile or
resistent enterococci, they can
transmit serious disease. If they harbor more ordinary bacteria or viruses,
they may transmit a less
serious illness.
[0003] One way to stay healthy is to reduce the bacteria count on the hands.
It is impossible,
even with an aggressive surgical scrub, to eliminate all of them. A unique
problem exists in the nail
beds, where accumulated oil and debris combine with sufficient amounts of
moisture to provide a
reservoir of bacteria. 95% of the bacteria on the hands reside in the nail
beds. In studies of healthy
adult hands (non-healthcare workers) samples from the palms and fingertips
show only hundreds to a
few thousand bacteria per square centimeter. A similar sample from the nail
beds reveals hundreds
of thousands of bacteria.
[0004] The tools available to reduce the number of bacteria on the hands
include water,
chemicals and friction. Rinsing or irrigating a surface will dilute the number
of bacteria. Early in
medical education we are taught that "dilution is a solution to pollution."
Operative sites are
copiously irrigated before closure. The more water the better.
[0005] Antimicrobial chemicals kill bacteria and viruses directly. Soaps and
detergents cut oil
and grease, facilitating the displacement of microorganisms as well as aiding
the penetration of
chemicals.
CA 02723652 2010-12-01
[0006] Friction may be generated by rubbing hands together, scrubbing with
brushes and
sponges and scraping the nail beds with files and picks. But even a standard
surgical scrub removes
only 60 to 80% of bacteria in the nail beds. Substantial numbers of pathogens
remain.
[0007] This problem is critical to healthcare workers, especially those who
participate in
invasive surgery. Patients need protection from bacteria and viruses
(hepatitis B and HIV) that may
be introduced through a punctured glove. Doctors and nurses need protection
from infected patients.
Routine hand washing and the use of alcohol based hand sanitizers are helpful,
but do not address
the nail beds, the most contaminated part of the hands.
[0008] Food handlers in restaurants and cafeterias can benefit from cleaner
hands. Many homes
can improve the safety of the hands they bring to the dinner table.
SUMMARY OF THE DISCLOSURE
[0009] In a first implementation, the present disclosure is directed to a hand-
washing system
powered by water. The hand-washing system includes: a work enclosure that
includes: an upper end
when the work enclosure is in use; a lower end when the work enclosure is in
use, the lower end
spaced from the upper end; a longitudinal central axis extending between the
upper end and the
lower end; a sidewall extending between the upper end and the lower end; a
closure substantially
closing the lower end; an interior space substantially defined by the sidewall
and the closure; and a
spray nozzle located at the upper end, the spray nozzle having an inlet, an
inlet water pressure at the
inlet during use, and a spray exit orifice configured to provide a spray of
water at an outlet flow rate
(Q) and a nozzle exit velocity (V) during use, the spray nozzle configured so
that 1) the outlet flow
rate is at least 0.7 gallons per minute when the inlet water pressure is 20
pounds per square inch and
2) the spray nozzle has a V/Q ratio of at least 20 gallons-per-minute per feet-
per-second, wherein the
spray exit orifice is oriented to direct the spray of water into the interior
space; wherein the sidewall
contains a digit portal receiving at least one digit of a hand of a human user
during use and
configured to allow the human user to point the at least one digit toward the
upper end during use of
the hand-washing system.
[0010] In a second implementation, the present disclosure is directed to a
hand-washing system.
The hand-washing system includes: a first work enclosure arranged according to
the work enclosure
of the first implementation and configured to be optimized for a first hand of
a first size, the first
work enclosure including a first quick-disconnect coupling; a second work
enclosure arranged
according to the work enclosure of the first implementation and configured to
be optimized for a
2
CA 02723652 2010-12-01
second hand of a second size different from the first size of the first hand,
the second work enclosure
including a second quick-disconnect coupling; a mixing valve for receiving hot
and cold water and
mixing the hot and cold water into a controlled-temperature mixture; a third
quick-disconnect
coupling; and a flexible conduit fluidly connecting the third quick-disconnect
coupling to the mixing
1_.,_. L_ L. of the first and second 14= on" ect couplings is configured to
fluidly
valve, herein each of the first and second .. lu,c.a-di$cu,vv~.Y"" bJ
couple, in seriatim, corresponding respective ones of the first and second
work enclosures to the
third quick-disconnect coupling so as provide the controlled temperature
mixture thereto.
[0011] In a third implementation, the present disclosure is directed to a
water-powered hand-
washing system for washing digits of a hand including four contiguous three-
phalanx fingers and an
opposing thumb. The water-powered hand-washing system includes: a work
enclosure that includes:
an upper end when the hand-washing system is in use; a lower end when the hand-
washing system is
in use, the lower end spaced from the upper end; a longitudinal central axis
extending between the
upper end and the lower end; a sidewall extending between the upper end and
the lower end; a
closure substantially closing the lower end; an interior space substantially
defined by the sidewall
and the closure; and a spray nozzle located at the upper end, the spray nozzle
having an inlet, an inlet
water pressure at the inlet, and a spray exit orifice configured to provide a
spray of water at an outlet
flow rate (Q) and a nozzle exit velocity (V), the spray nozzle configured so
that the outlet flow rate
is at least 1.5 gallons per minute when the inlet water pressure is 40 pounds
per square inch and the
spray nozzle has a VIQ ratio of at least 30 gallons-per-minute per feet-per-
second, wherein the spray
exit orifice is oriented to direct the spray of water into the interior space,
the spray nozzle configured
to provide a fan-shaped spray having an included angle of at least 25 ;
wherein the sidewall contains
a digit portal spaced from the closure so as to define an energy dissipation
region for containing a
reservoir of water for dissipating energy in the spray of water when the hand-
washing system is
operating in an upright position with the upper end located above the lower
end, the digit portal
having a laterally elongate finger receiving-region for receiving
simultaneously the four three-
phalanx fingers in a closed-fingered, upwardly curled arrangement, and further
having a thumb
notch extending toward the upper end of the work enclosure, the thumb notch
for receiving the
thumb in an orientation that allows the human user to point the tip of the
thumb toward the upper
end of the work enclosure.
[00121 In a fourth implementation, the present disclosure is directed to a
method of washing all
five digits of a human hand. The method includes: providing the work enclosure
of the third
implementation; providing temperature-controlled water to the spray nozzle of
the work enclosure so
CA 02723652 2010-12-01
that the inlet water pressure of the spray nozzle is at least 20 pounds per
square inch, the outlet flow
rate is at least 0.7 gallons per minute and the nozzle exit velocity is at
least 45 feet per second;
holding the work enclosure in a substantially upright orientation; inserting,
simultaneously with one
another and through the elongate finger-receiving region, the four three-
phalanx digits into the
e-
t 'or the closed lllgered nrdly curled nrran ent = rovid g the temp rature
ILl er IVl space Ill the ~1Va%1%4_ , upwardly Ull Glllgel lt+ll~ while
Y'1llll. V1Wvl\ lnr, the wu1jJ,lul.ul~.-
controlled water to the spray nozzle; allowing the spray of water to impact
upon the four three-
phalanx digits for a period of time; removing the four three-phalanx digits
from the interior space;
inserting the opposing thumb into the interior space via the thumb notch so
that the tip of the
opposing thumb is pointing substantially toward the upper end of the work
enclosure while
providing the temperature-controlled water is provided to the spray nozzle;
allowing the spray of
water to impact upon the opposing thumb for a period of time; removing the
opposing thumb from
the interior space; and stopping flow of the temperature-controlled water to
the enclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[00131 For the purpose of illustrating the invention, the drawings show
aspects of one or more
embodiments of the invention. However, it should be understood that the
present invention is not
limited to the precise arrangements and instrumentalities shown in the
drawings, wherein:
FIG. I is a partial cross-sectional view/partial elevational view of a water-
powered hand-washing
system installed in a household kitchen sink setting;
FIG. 2 is an enlarged vertical cross-sectional view of the work enclosure of
the water-powered hand-
washing system of FIG. 1;
FIG. 3 is an enlarged vertical cross-sectional view of the work enclosure of
FIG. I illustrating an
orientation of a finger inserted into the work enclosure for cleaning;
FIG. 4 is an enlarged vertical cross-sectional view of the work enclosure of
FIG. 1 illustrating an
orientation of a thumb inserted into the work enclosure for cleaning; and
FIG. 5 is an enlarged partial cross-sectional view/partial elevational view of
a quick-disconnect
coupler/nozzle assembly configured to receive a pill for dispensing a washing
agent to a work
enclosure of a water-powered hand washer, such as either of the work
enclosures of FIG. 1, when the
assembly is coupled to such an enclosure.
4
CA 02723652 2010-12-01
DETAILED DESCRIPTION
[0014] The present disclosure is directed to water-powered hand-washing
systems and
components therefor that provides significant advantages over conventional
water-based hand-
washing devices known to the present inventor. Important among these
advantages is the fact that a
L. ' .. the t -liscl provides excellent cleaning -effectiveness, especially
hand-washing system of f the pr%seiiL uJsclos ure exce vl eW.ing 1..
in the ability to dislodge and remove large fractions of bacteria and other
foreign matter from
fingernail beds and cuticular regions of fingers and thumbs with relatively
little effort on the user's
part, as compared to conventional cleaning methods, such as scrubbing with a
nail brush. Another
important advantage is that this cleaning effectiveness can be achieved at
conventional domestic
water supply pressures, for example, from about 20 pounds per square inch
(PSI) to about 50 PSI.
Other important advantages and improvements over conventional hand-washing
devices, systems
and methods will become apparent upon reading the following disclosure.
[0015] Turning now to the drawings, FIG. 1 illustrates an example of a water-
powered hand-
washing system 100 made in accordance with broad concepts disclosed herein. In
this example,
hand-washing system 100 is shown in a home-kitchen environment wherein it is
integrated into a
kitchen-sink installation 104. As such, hand-washing system 100 is readily
available for use by
virtually all members of the corresponding household, except perhaps for the
very youngest of
children. Installing a hand-washing system of the present disclosure in a
central location, such as in
a kitchen, is desirable because in some embodiments an important aspect of the
system is that it be
used routinely by all members of the household throughout the day, especially
following any
activity, such as gardening and preparing meals from raw meat, in which
fingernail beds and
cuticular regions become particularly dirty and/or are exposed to bacteria-
laden/bacteria-promoting
matter and especially before engaging in an activity, such as eating and
dental flossing, where any
bacteria and/or other undesirable matter present in fingernail beds and
cuticular regions could easily
enter a human body.
[0016] As those skilled in the art will readily appreciate, a home-kitchen
environment, such as
installation 104 of FIG. 1, is only one example of a location suitable for
containing a water-powered
hand-washing system made in accordance with one or more of the broad concepts
of the present
disclosure. Other examples of environments where installation of a system of
the present disclosure
would be beneficial include, but are not limited to, commercial kitchen
environments to assist in the
cleaning of hands of cooks and other food handlers so as to inhibit the spread
of bacteria and other
undesirable matter among food items and work areas, and health care
environments to assist
CA 02723652 2010-12-01
surgeons, physician's assistants and nurses in preparing for surgery or
providing hands-on patient
care so as to reduce the likelihood of contaminating the patient and risking
infection. Indeed, and as
described below, some of the broad concepts of the present disclosure are
directed to features that
will contribute to the efficacy of such systems not only in home and kitchen
use, but in use in
~~~~r~L gic l settin where the cleanliness renuiramVli l~l ents are much more
critical So all oft these
"I J\+11111g0 w he- 1.11V Vl V(Alll111 V J 11 1V me or hese
J61
features are lacking in various ones of conventional finger/thumb/hand
cleaning assistance devices
of which the present inventor is aware.
100171 With continuing reference to FIG. 1, primary components of hand-washing
system 100
include a mixing/flow valve 108, a work enclosure 112 and a flexible conduit
116 that fluidly
connects the work enclosure to the mixing valve. Mixing/flow valve 108 is
fluidly connected to
each of a cold water supply line 120 and a hot water supply line 124, which
may be any conventional
domestic water supply lines, such as half-inch household lines that typically
deliver a maximum of
1.8 gallons per minute (GPM) (California plumbing regulations) to 2.5 GPM (the
rest of the U.S.)
within a range of 20 PSI to 60 PSI. Typically, the hydrostatic pressure
available in household water
lines ranges from 20 PSI to 50 PSI, with an average range of about 35 PSI to
45 PSI in most
municipal lines and 35 PSI to 40 PSI in most well or domestic, pump-driven
lines.
[00181 When in use, mixing/flow valve 108 mixes cold and hot water from,
respectively, cold
and hot water supply lines 120, 124 so as to provide a desired/suitable
temperature to the mixed
output water, which flexible conduit 116 then provides to work enclosure 112.
A thermostatic
cartridge with mixing/flow valve 108 can protect users from scalding by
limiting the maximum hot
water temperature provided. Mixing/flow valve 108 also allows a user to adjust
the flow of water
provided to work enclosure 112 so as to optimize the cleaning conditions and
user comfort of the
spray within the enclosure. Mixing/flow valve 108 may be any suitable mixing
valve. An example
of a suitable mixing valve is the mixing valve portion of the Kohler HIRiseTM
sidespray unit model
K-7344-4, available from Kohler Company, Kohler, Wisconsin. Of course, that
unit would have to
be modified to receive flexible conduit 116 rather than the sidespray assembly
accompanying the
valve. In a particular example, the modified unit includes flexible conduit
116 in a length of
28 inches measured from the base at the countertop to the shutoff valve (164).
Of course, any one of
many other mixing valves could be used. A constraint on the choice of mixing
valves for use as
mixing valve 108 is that the selected valve must be able to provide the water
pressures and flow rates
described below that are needed to provide hand-washing system 100 with it
cleaning effectiveness.
6
CA 02723652 2010-12-01
[00191 As will become apparent from reading the following description, during
use work
enclosure 112 is designed to be oriented as shown in FIG. 1. As such, during
use work
enclosure 112 has an upper end 128 and a lower end 132. Primary components of
work
enclosure 112 include a sidewall 136, a bottom closure 140 and a spray nozzle
144. In the example
a by sidewall 3 6 128 of work 1, showri, the openng 1ormteU 1376 at Upper end
d IGO v1 work eneo sure sure r 12- is than
the diameter of spray nozzle 144. Consequently, this example includes a top
closure 148 to close the
region between nozzle 144 and sidewall 136 so as to prevent backspray from
exiting upper end 128
of work enclosure 112. In other embodiments, the upper end of the sidewall and
corresponding
spray nozzle may be designed so that the interface between the nozzle and
sidewall obviates the need
for any additional closure at the upper end of the work enclosure. Sidewall
136 includes a "digit"
portal 152 ("digit" referring to the digits of a human hand, i.e., the fingers
and thumb) that allows a
user to insert one thumb or four fingers into the interior of work enclosure
112 in a proper manner
(see below). Further details of work enclosure 112 are described below in
connection with FIGS. 2-
4.
[00201 Referring now to FIG. 2, work enclosure 112 is configured to receive
the proximal,
intermediate and distal phalanges of all four fingers simultaneously so that
these four fingers can be
cleaned substantially simultaneously with one another. To facilitate this
simultaneity, digit portal
152 includes a laterally elongate finger-receiving slot 152A sized to
accommodate these four fingers
up to and including their proximate phalanges when these fingers are in loose
contact with one
another and inserted into work enclosure 112 in an upwardly curled manner as
illustrated by finger
300 in FIG. 3. In this work position, the intermediate and distal phalanges of
these four fingers are
wholly contained within work enclosure 112. It is noted that in alternative
embodiments in which all
three phalanges of all four fingers may be inserted into the work enclosure at
once, the work
enclosure may be configured so that the user inserts his hand more than or
less than shown in FIG. 3.
For example, in some other embodiments the work enclosure may be configured
for the user to
insert their hand up to or past the metacarpophalangeal joints of those four
fingers. Some other
embodiments may be configured for the user to insert those four fingers only
to their intermediate
phalanges or their proximal interphalangeal joints.
[00211 Referring back to FIG. 2, dashed line 200 indicates the periphery of
the approximate
space occupied by the portion of the hand (here, the proximal phalangeal
portion) that extends
through digit portal 152 when an adult hand of 95-percentile breadth (e.g.,
3.9 in. (9.8 cm) based on
U.S. statistics) is properly positioned relative to work enclosure 112. In the
example of FIGS. 1-3,
7
CA 02723652 2010-12-01
when the four three-phalanx fingers of one of the user's hands are inserted in
an upwardly curled
manner as illustrated in FIG. 3, the user may be holding work enclosure 112
with the opposite hand
by, for example, grasping the necked-down upper portion of the enclosure with
the thumb and index
and middle fingers. In alternative embodiments, the work enclosure could be
secured to a
=ixture (not shown) or fieeS+-A
[0022] Spray nozzle 144 is either designed or selected to provide high
volumetric flow rates and
high outlet velocities across a range of delivery pressures. In the example
shown, spray nozzle 144
has an outlet orifice 204 configured to provide a fan-shaped spray pattern
208, which is an effective
shape because of the generally linear arrangement of the tips of the four
three-phalanx fingers when
they are in their work position as described above. The magnitude of included-
angle 0 (theta) may
be selected based on the distance of the fingertip-receiving region (denoted
by its outline 212) within
work enclosure 112 from spray nozzle 144 (here, about 1.5 inches to 2 inches).
The four fingers,
once inserted, are moved side-to-side (here, about 0.75 inches to about 1
inch) to expose all surfaces
to the full force of the high-velocity, high-flow-rate stream from spray
nozzle 144. Based on the
configuration of work enclosure 112 and working position of the hand within
the enclosure, an
acceptable included angle 0 would generally fall in a range of about 30 (01)
to about 60 (02). In
other embodiments having configurations different from the configuration of
work enclosure 112,
the included angle of the corresponding spray patterns may be outside the
range shown.
[0023] As seen in FIG. 3, in the direction perpendicular to the fan shape,
spray pattern 208
remains fairly concentrated. That is, spray pattern 208 has very little spread
as the spray moves
away from outlet orifice 204. This narrowness allows the force of the spray to
be as concentrated as
possible in the fingertip-receiving region 212 where the user's digit tips
will be located during
cleaning. With spray pattern 208 remaining fixed and being relatively narrow
in a plane
perpendicular to the planes in which the fingers are positioned while present
inside work
enclosure 112 (i.e., the vertical plane into and out of the page containing
FIG. 3), it can be
appreciated that for the user to achieve the best cleaning results the user
should slowly flex and
extend the fingers and move them side-to-side (again, about 0.75 inches to
about 1 inch in this
example) to expose palmar surfaces, fingernail beds, cuticular regions and
lateral surfaces to the
spray for an effective amount of time (such as 30 seconds to 40 seconds or
more).
[0024] Referring again to FIG. 2, and also to FIG. 4, this example of digit
portal 152 further
includes a thumb notch 152B designed to accommodate the user's thumb 400 (FIG.
4) during
8
CA 02723652 2010-12-01
washing. FIG. 4 illustrates one way that the user can insert thumb 400 into
work enclosure 112, i.e.,
with the thumbnail generally facing the "front" of the work enclosure.
Alternatively, the thumb may
be inserted with the thumbnail facing the "back" of work enclosure 112. In
either position the thumb
can be gently flexed or extended to provide thorough exposure of the palmar
surface, fingernail bed,
cuticular surface and lateral surfaces to the spray for an effective amount of
time (e.g., 20 seconds
total or more). The choice of thumb orientation will generally depend on
factors such as the
location/locatability of work enclosure 112 relative to the user during
washing and whether or not
the user is holding the work enclosure with the opposite hand during washing.
100251 With thumb 400 being generally more limited in terms of range-of-motion
and
positionability relative to the three-phalanx fingers, thumb notch 152B allows
the user to position the
tip of the thumb in fingertip-receiving region 212 where the tips of the three-
phalanx fingers are
located during washing. When thumb 400 is inserted into work enclosure 212 as
shown in FIG. 4,
the particular configuration of this work enclosure has roughly the entire
distal phalanx of the thumb
located within the enclosure. In other embodiments, it may be necessary to
design the work
enclosure so that some or most of the proximal phalanx of thumb 400 is also
located within the
enclosure. When thumb 400 of the user's one hand is inserted into work
enclosure 112 as shown in
FIG. 4, the user may be holding the work enclosure with the other hand, for
example, as described
above relative to the washing of the four three-phalanx fingers.
Alternatively, work enclosure 112
may be secure to a fixture or free-standing.
[00261 As mentioned above, a hallmark of a water-powered hand-washing system
of the present
disclosure is the exposing of finger tips, especially the palmar surfaces,
fingernail beds and cuticular
regions, to high-impact-energy, high-flow-rate water spray. To this end, in a
particular example
suited for the particular configuration of working enclosure 112 shown in
FIGS. 2-4 (with the
various figures being largely in scale relative to finger 300 and thumb 400 of
FIGS. 3 and 4,
respectively), spray nozzle 144 is standard fan nozzle model '/4"NF 1530 (30
fan) available from
BETE Fog Nozzle, Inc., Greenfield, Massachusetts. The 1/4"NF 1530 nozzle has
the performance
characteristics appearing in the following Table.
TABLE
Performance Characteristics of BETE 30 Fan Nozzle Model '/4"NF1530
Inlet Pressure (P) Outlet Flow (Q) Exit Velocity (V) V/Q
(PSI) (GPM) (ft/s (FPS)) ((FPS)/(GPM))
0.75 34.7 46.3
1.06 49.0 46.2
9
CA 02723652 2010-12-01
30 1.30 60.1 46.2
40 1.50 69.4 46.3
50 1.68 77.5 46.1
60 1.84 85.2 46.3
[0027] The performance characteristics of the BETE '/4"NF1530 spray nozzle
listed in the
preceding Table provide hand-washing system 100 (FIG. 1) with very good
cleaning performance.
Observations of test users have revealed that, with the BETE '/4"NF 1530
nozzle, its spray at an
inlet pressure of about 20 PSI is well-tolerated by children. Adult test users
have found its spray at
about 35 PSI to about 50 PSI to be comfortable and invigorating. In this
connection, it is noted that
mixing/flow control valve 108 allows users to adjust the spray output by spray
nozzle 144 to a
comfortable, yet effective level, generally between about 10 PSI (0.75 GPM for
the BETE(X
'/4"NF1530 nozzle) to about 58 PSI (1.8 GPM for the BETE '/4"NF1530 spray
nozzle (again, 1.8
GPM is the current maximum flow rate under California standards)). Operation
at pressures higher
than 58 PSI with the BETE '/4"NF1530 spray nozzle is possible depending on
code regulations
(such as the 2.5 GPM maximum in U.S. states other than California) and whether
a particular user
can tolerate the resulting higher spray velocities.
[0028] As mentioned above, the cleaning effectiveness of hand-washing system
100 is due in
large part to dilution and debridement accomplished by subjecting the target
digit(s) to both high
water flow (dilution) and high-impact water velocity (debridement). Regarding
water flow rates, it
is desired that the flow rate be at least about 0.75 GPM and more preferably
at least about 1.3 GPM,
with values up to 1.8 GPM (California standard) or 2.5 GPM (non-California
states' standard)
typically being more desirable as long as the resulting higher velocities are
tolerable by a particular
user. Regarding nozzle exit velocity, which correlates with impact force of
the spray upon the
digit(s) placed in fingertip-receiving region 212 (FIGS. 2-4), it is desirable
that the exit velocity be at
least about 40 feet per second (FPS) during cleaning, regardless of outlet
flow rate or inlet pressure.
For adults having the digit closest to the exit orifice of nozzle 144 about
1.5 inches to 2 inches from
exit orifice 204, the exit velocity is more preferably at least about 60 FPS.
[0029] A convenient way to express the relationship between exit velocity (V)
and outlet
flow (Q) for any nozzle is to calculate the V/Q ratio. As seen from the Table
above, for the BETE
'/4"NF 1530 spray nozzle the V/Q ratio is largely constant, here about 46.3
FPS/GPM, over the range
of inlet pressures appearing in the Table. It is recognized that water spray
nozzles suitable for use as
nozzle 144 other than the BETE `/4"NF 1530 nozzle will have performance
characteristics different
CA 02723652 2010-12-01
from the performance characteristics of the'/4"NF1530 nozzle presented in the
Table above. For
example, not only can the V/Q ratio be different, but the outlet flow rates Q
and exit velocities at
particular pressures can be different, too. For example, a suitable
alternative nozzle may provide a
flow rate of 1.6 GPM at 30 PSI and have a corresponding outlet velocity of 70
FPS (here, V/Q
would be about 43.8 FPS/GAM. Regardless of the nozzle used, it is beneficial
for the V/Q ratio,
when V is expressed in FPS and Q is expressed in GPM, to be at least about 20
FPS/GPM and more
preferably at least about 30 FPS/GPM.
[00301 When hand-washing system 100 (FIG. 1) is operating within the intended
ranges of flow
rates and velocities, the water output of nozzle 144 can be equated to output
of a conventional
garden-hose nozzle outputting 1.8 GPM in a fairly tightly focused pattern at a
line-pressure of
45 PSI. As one can imagine, the output rate and forcefulness of spray nozzle
144 is quite
substantial, especially for a device intended for use inside homes, in
commercial kitchens and in
surgical scrub areas, among other places. In this connection and referring
again to FIG. 2, work
enclosure 112 includes an energy-dissipation region 216 that, during use,
defines an energy-
dissipating reservoir of water 216A for rapidly dissipating energy in the high-
velocity water spray
from nozzle 144 during use, both when one or more digits are properly inserted
into the work
enclosure and being washed and when the nozzle is spraying water without any
digits present within
the work enclosure. The latter situation can occur if the nozzle is still
operating but the user does not
have any digits inside enclosure 112, such as just before or just after a
washing operation.
[0031] As seen in FIG. 2, dashed line 220 indicates that when a hand is
properly engaged with
work enclosure 112, a gap exists between the lower edge 224 of sidewall 136
and the hand-occupied
region of digit portal 152. FIG. 3 illustrates that when hand-cleaning system
100 is operating, this
configuration allows reduced-energy water 304 to fairly gently exit work
enclosure 112 and fall to a
suitable location, such as a sink, for example, sink 156 of FIG. 1, without
interfering with the
insertion or removal of any of the digits during a cleaning operation. It is
noted that in alternative
embodiments, bottom closure 140 and/or sidewall 136 near lower end 132 can
each be provided with
one or more apertures to partially or fully handle the outflow of water from
within work
enclosure 112 during use. That said, for the sake of easily maintaining the
cleanness of work
enclosure 112, the fewer apertures, especially relatively small apertures
having reentrant
corners/small radii, the better, since contaminants tend to build up in such
areas, even with moderate
cleaning.
11
CA 02723652 2010-12-01
[0032] A large part of the energy-dissipation capability of energy-dissipation
region 216 is due
to the depth D of the pool 228 of water that eventually collects in the energy-
dissipation region.
Depth D should be great enough that the force of the spray striking pool 228
at full spray without
any digits present within enclosure 112 does not part water 228 all the way to
bottom closure 140.
r 1 E~ i"NF1 15 3 V n nozzle le UJII escriIUGb_.7U above, an adequate
.7gadequate a + . u~ ~ epti 1. i Ln LItl.L at pi rovides ple
For the tS n 30 %41V r
v iuw aM.l ,
energy dissipation is about 1.5 inches. Somewhat lesser depths could likely be
tolerated, as could
greater depths. If additional apertures are provided to work enclosure 112 as
mentioned above, care
should be taken to avoid placing them in the direct path of spray pattern 208
if they are un-baffled
because the spray will tend to exit the work enclosure forcefully through such
apertures until enough
depth has built up in pool 228.
[0033] FIG. 3 illustrates two configurations of sidewall 136 near spray nozzle
144. The first
configuration (shown in solid lines) is a straightforward configuration that
includes a gentle tapering
of sidewall 136 from its widest region (relative to the view of FIG. 3) near
digit portal 152 to its
narrowest region near nozzle 144. The second configuration (shown in dashed
lines) includes a
"pinched" region 308 near nozzle 144 that inhibits backsplashing from the
impact of the spray issued
by the nozzle upon one or more digits present in fingertip-receiving region
212. By inhibiting such
backsplash, contamination of nozzle 144 and regions immediately surrounding
the nozzle can be
reduced.
[0034] Further regarding the cleanness of work enclosure 112, several features
of this enclosure
provide it with excellent cleanability. In surgical and other patient-care
settings, it is likely that work
enclosure 112 will be sterilized between uses or top closure 148 with nozzle
144 and the female
portion of quick-disconnect assembly (160) will be sterilized and the lower
work enclosure (here,
sidewall 136 and bottom closure 140) disposable. In the home setting there are
several features that
facilitate disassembly and cleaning, including: 1) readily removable bottom
and top closures 140,
148 (FIG. 1); 2) smooth interior to sidewall 136 that contains few, to no,
reentrant corners and other
contaminant-trapping structures; 3) simply shaped sidewall that allows easy
access to all internal
surfaces of the sidewall by, for example, a bottle brush and 4) simply shaped
internally facing
surfaces of the bottom and top closures.
[0035] Regarding materials of construction of the various components of work
enclosure 112,
each of the components may be made of any material(s) suitable for that
component. For example,
sidewall 136 may be made of metal, plastic or composite, or any combination
thereof, as may be
12
CA 02723652 2010-12-01
bottom and top closures 140, 148. Likewise, nozzle 144 may be made of metal,
plastic or
composite, or any combination thereof. Considerations for selecting materials
include strength,
weight, durability and cost, among others.
[00361 Referring again to FIG. 1, in this example hand-washing system 100
includes a quick-
disconnect assembly 160 and a shutoff valve 164 that provide the system with
great flexibility. The
combination of these two elements allows work enclosure 112 to be quickly and
easily coupled to
and decoupled from flexible conduit 116 for any of a variety of reasons
without having to change the
setting on mixing/flow valve 108. For example, if hand-washing system 100
includes a second work
enclosure, such as child-sized work enclosure 168 (whereas work enclosure 112
is an adult-sized
work enclosure), a user could readily switch between the differing work
enclosures. In this example,
it is noted that work enclosure 168 has all of the features of work enclosure
112, but is sized for
smaller hands, such as hands of young children.
[00371 Quick-disconnect assembly 160 can be any suitable quick-disconnect
assembly, such as
a quick-disconnect assembly that includes a suitable combination of male and
female couplings, for
example, the male and female quick-disconnect couplings available from
McMaster-Carr, Atlanta,
Georgia. Those skilled in the art will readily appreciate that the variety of
quick-disconnect
couplings is large and the choice of these couplings will depend on things
such as the configuration
of nozzle 144 (e.g., interiorly, exteriorly threaded, barbed, etc.), the
configuration of the immediately
adjacent upstream component (here, shutoff valve 164) (e.g., interiorly,
exteriorly threaded, barbed,
etc.) and design choice.
100381 Similarly, shutoff valve 164 can be any suitable shutoff valve, such as
a simple ball
valve or stop cock. In other, more elaborate embodiments, the shutoff valve
(if provided) can be a
lever-type valve of the type commonly found on commercial kitchen utility
spray assemblies
adjacent the spray heads. An example of such a spray valve having a lever-type
valve is the FIS-
2946 spray valve available from Fisher Manufacturing Company, Tulare,
California. It is noted that
shutoff valve 164 need not be provided. In such embodiments, if having a water
shutoff feature
independent of mixing/flow valve 108 is desired, for example, for swapping
work enclosures 112,
168 with one another, a type of quick-disconnect valve that shuts off flow
when the male and female
components are disconnected from one another may be used.
[00391 FIG. 5 illustrates a particular quick-disconnect assembly/nozzle
arrangement 500 that
can be used with a work-enclosure made in accordance with the broad concepts
described above,
13
CA 02723652 2010-12-01
such as either of work enclosures 112, 168 of FIG. 1. Quick-disconnect
assembly/nozzle
arrangement 500 allows a user to enhance the cleaning performance of a hand-
washing system of the
present invention by dispensing a washing agent (e.g., soap, detergent,
sanitizer, etc., and any
combination thereof) into the water flow that reaches the user's digit(s)
present in the work
enclosure (not enclosure (not shown). 'in tUhi1J n example, ' t
assembly/nozzle arr ngem ent 500
lqulClC-d1JVVlLleca uJJVUaIIa,uvL.[.av aaaaasv avau
comprises a quick-disconnect assembly 504 and a spray nozzle 508. Quick-
disconnect assembly 504
includes a male coupling 510 and a female coupling 512 that removably engage
one another in a
conventional manner. In this example, female coupling 512 includes a body 516
and a sleeve 520
that is movable longitudinally relative to the body. When a user desires to
uncouple male and
female couplings 508, 512 from one another, the user moves sleeve 520 in the
appropriate direction
so as to initiate the disengaging process. Arrows 524 indicate the directions
of movement of male
coupling 510 during engagement and disengagement of the male coupling relative
to female
coupling 512 (assuming female coupling is fixed in space). Alternatively, some
designs permit
uncoupling to be initiated by a convenient button on the side of the female
component. The
Standard Push-Button Socket model no. 5163T11, available from McMaster-Carr,
displays this
feature.
[0040] In this example, body 516 of female coupling 512 includes a
longitudinal central
passageway 528 and an integral annular stop 532. Stop 532 provides a first
shoulder for engaging a
sealing gasket 536 between female coupling 516 and spray nozzle 508 and a
second shoulder for
engaging a screen assembly 540. Here, screen assembly 540 includes a screen
544 and an annular
resilient gasket 548 that has a slight interference fit with passageway 528 so
as to hold the assembly
in place within the passageway. In this example, the washing-agent dispensing
feature is
implemented by a user inserting a washing-agent pellet or pill 552 into
passageway 528 upstream of
screen assembly 540. It is noted that the word "pill" is used herein and in
the appended claims for
convenience to denote both a self-contained mass of one or more pure washing
agents and a self-
contained mass of one or more pure washing agents in combination with one or
more fillers, one or
more binding agents, one or more additives, and/or a containment structure
(e.g., a gel capsule), and
any combination thereof. Pill 552 should have an appropriate shape that does
not significantly
impact the flow rate through female coupling 516.
100411 In a typical scenario, a user inserts washing-agent pill 552 into
passageway 528 by
disengaging male coupling 510 from female coupling 512, places the pill into
the passageway and
re-engages the male coupling with the female coupling. During operation of the
hand-washing
14
CA 02723652 2010-12-01
system of which quick-disconnect assembly/nozzle arrangement 500 is made a
part, water (not
shown) flowing through passageway 528 slowly dissolves washing-agent pill 552
and causes the
output (not shown) of spray nozzle 508 to contain the dissolved portion of the
pill. In one
embodiment, pill 552 is designed to dissolve in an amount of time equal to, or
roughly equal to, the
amount t Vl l f tillll RllmeV anticiated for a N typical w~rash cyrcle either
for one hand or both hands as desiredI
llVlpl.lul~U for t.F-l _- -.7 , v ,
Other types of washing-agent dispensing arrangements are possible, such as an
arrangement that
uses a venturi eductor to draw a washing agent into the water flow before it
is ejected into the work
enclosure. Those skilled in the art will understand how to provide such
alternative washing-agent
dispensing arrangements to a hand-washing system made in accordance with the
present disclosure.
[00421 Some of the foregoing advantages have been demonstrated in a trial
performed in a
hospital setting. In this trial a group of surgeons and lab technicians had
selected fingers cultured to
quantify the bacterial count present on their hands after performing their
standard hand-washing
procedure. The test subjects were then given brief instructions on using a
device embodying the
concepts of the present disclosure, and then used the device to clean their
hands. The same selected
fingers were cultured again to quantify the reduction in bacterial count
accomplished by the device.
The results of the trial appear below in TABLE 1.
S[_113JI (T I' DIGIT ('L;Ii/M I_ C.MI I,i't91. IZE;I)[_'C"LION
I3FI'{JRI AF'TER
A Index 888.000 21 ,600 98.6
Middle 27 300 300 99.9
Thumb 855.000 492.000 57.7
13 Index ,9 4.000 6.900 99.8
Middle 75.900 300 99.7
Thumb 681,000 5.1 00 99.3
C Index 1 17,O(}O 2,100 98.8
Middle 44,400(} <300 100
Thumb 480.000 2,520 99.5
I) Index 71.000 600 99.2
Middle 3180{~ 1,500 95.3
Thumb 9,900 41.400_._ 418 GAIN
F Index 10,200 4,500 55.9
Middle 9,000 600 93.4
1 humb 54.900 900 98.4
F Index 1.500 <300 100
:diddle _),900 1.500 61.6
Thumb 27.900 900 96.8
C Index <300 <300
Middle 32.800 30(1 99.9
Ihumb 300 <300
CA 02723652 2010-12-01
----------- - -
H Index 2,100 <300 100
Middle 300 <300 100
Thumb 1,800 <300 100
W Index 129,000 15.300 98.8
Middle 834.000 12.600 98.5
't'humb 3.000 300 100
' 000 8 inn 98 F.
)C lldeX ? l.vvv o, i vv u.v
Middle 252,000 4,500 98.2
Thumb 11,700 900 92.4
y Index 24,30() 1,200 95.1
Middle 9,000 <300 100
Thumb 144,000 16,200 88.9
Z Index 12,900 24.600 190% GAIN
Middle l ,j{)0 18.900 1260% GAIN
Thumb 150,000 1,200 99.1
100431 TABU" 1
[0044] While the data show a market decrease in almost all cases, three cases
show an increase
in bacteria count after using the water-powered hand-washing system. It is
likely that these samples
were mis-labeled during processing.
[0045] Exemplary embodiments have been disclosed above and illustrated in the
accompanying
drawings. It will be understood by those skilled in the art that various
changes, omissions and
additions may be made to that which is specifically disclosed herein without
departing from the
spirit and scope of the present invention.
16
