Note: Descriptions are shown in the official language in which they were submitted.
MIX ON DEMAND SMART BACKPACK SPRAYER
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of pending United
States patent application
Ser. No. 15/725,937 filed October 5, 2017, and entitled "MIX ON DEMAND
SPRAYER," the
contents of which are fully incorporated herein.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a sprayers, and more
particularly to a
sprayer configured to dilute a fluid concentrate with a diluent prior to
spraying, and still more
particularly to a mixing manifold selectively and changeably metered to inject
a measured dose of
the fluid concentrate into the diluent to produce a mixed fluid with a desired
concentrate dilution.
In a further aspect of the present invention, the present invention generally
relates to sprayers, and
more particularly to a backpack sprayer, and still more particularly to a
backpack sprayer
incorporating smart controls and enhanced fluid control systems.
BACKGROUND OF THE INVENTION
[0003] Sprayers, such as broadcast sprayers are used across an array of
applications,
including farms, golf courses and residential properties, to apply water or
other liquids, such as
pesticides including herbicides, insecticides and the like. As such, these
sprayers may need to
cover a large area and, therefore, generally include large tanks strapped to a
vehicle, such as an all-
terrain vehicle (ATV) or golf cart, or may be mounted onto a tow-behind
trailer. Typically in use,
these tanks are filled with a selected fluid composition that is to be
applied. By way of example,
pesticide solutions may be anywhere from about 1% to about 10% active chemical
in water. In one
scenario, a user may spray a diluted herbicide solution, such as to target
thistle. However, to apply
a second pesticide solution, such as a diluted insecticide to fruit trees, the
user will first have to
completely empty the tank of the herbicide solution before rinsing the tank of
any residual
chemicals and finally refilling the tank with the desired insecticide
solution. As may be readily
apparent from the above, there are numerous drawbacks to such systems. For
example and without
limitation, such drawbacks may include waste of chemicals, the need for
controlled disposal of
unused chemicals, the time consuming need to thoroughly clean the tank between
applications and
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the potential for cross-contamination and application of unwanted chemicals
after incomplete or
unsuccessful cleaning of the tank.
[0004] To alleviate some of the above-referenced drawbacks of broadcast
sprayers, systems
have been developed which segregate the chemical portion from the
water/diluent portion of the
system. In such systems, the chemical is stored in a smaller, separate tank
than the large water
tank. Metering devices may then add chemical to a flow of water prior to
emission from a wand or
boom sprayer. In this manner, the chemical remains isolated from the water
tank, thereby
minimizing or avoiding possible contamination of the water source. However,
heretofore systems
require complex plumbing regimes and interconnectivities of the various
components making such
systems difficult to use and burdensome to operate and clean.
[0005] Broadcast sprayers have also been configured as variable pressure
sprayers which
may selectively spray fluid from either a spray wand or through a boom-and-
nozzle arrangement
where multiple nozzles may be supported on a boom. Due to the multiple nozzles
within the
boom-and-nozzle arrangement, fluid must be delivered at high pressure so as to
enable proper
spraying at each of the individual nozzles. However, a spray wand uses a
single nozzle and may
become damaged if it receives high pressure fluid. To that end, current
systems typically use
pumps with a high pressure cut out switch. These systems are configured with a
recirculation
manifold whereby excess flow from the pump is diverted back to the supply
tank. A valve and
pressure gauge is provided on the manifold so the user can tune the percentage
of flow going back
to the tank while maintaining adequate pressure for the lower flow application
(spray wand).
Without providing for this recirculation pressure bleed off in the low flow
application, pressure
would build quickly and rapidly cycle the pressure cut off switch. A situation
that is detrimental to
both the switch and the pump. However, such a system should not be used in two-
tank systems as
the mixed fluid exiting the pump would be recycled to the water tank, thereby
contaminating the
water tank and changing the concentration of the chemical that is being
sprayed.
[0006] Beyond broadcast sprayers, backpack sprayers are also used to
apply water or other
liquids, such as pesticides including herbicides, insecticides and the like.
As the name implies,
backpack sprayers are designed to be worn by the user, such as through
securing a tank of the
sprayer against the user's back via one or more shoulder straps. A handheld
spray wand is fluidly
coupled to the tank and is manually actuated, such as through a trigger, to
dispense fluid from the
tank through the spray wand. Backpack sprayers may be configured as battery-
powered, variable
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pressure pump sprayers that may selectively spray fluid from the spray wand at
different pressures.
Typically, a positive displacement pump, such as a diaphragm pump, is powered
by the battery to
draw fluid from the various fluid tanks and deliver the pressurized fluid to
the wand nozzle to be
sprayed. However, currently available backpack sprayers only afford spraying
at differing
pressures and do not allow the chemical/diluent ratio to be changed.
[0007] Thus, there remains a need for a backpack sprayer with smart
controls that also
segregates the chemical tank from the water tank while providing selective and
variable dilution of
the chemical during application. The present invention satisfies this as well
as other needs.
SUMMARY OF THE INVENTION
[0008] In view of the above and in accordance with an aspect of the
present invention, the
present invention is generally directed to a sprayer system comprising a first
tank configured to
hold a diluent; a mounting bracket mounted to the first tank; and a second
tank removably mounted
to the first tank and configured to hold a liquid concentrate. A mixing
manifold is mounted to the
mounting bracket and has a first inlet fitting configured to receive a fixed
amount of diluent from
the first tank and a second inlet configured to receive a selectively
adjustable amount of liquid
concentrate from the second tank. The fixed amount of diluent and selectively
adjustable amount
of concentrate are combined to form a mixed solution. The mixing manifold
includes a mixed
solution outlet and a positive displacement pump is mounted to the mounting
bracket and has a
suction port fluidly coupled to the mixed solution outlet. A pressure port is
configured to fluidly
couple with a spray device. The second tank may be separable from the first
tank without requiring
removal of the mixing manifold or positive displacement pump.
[0009] In a further aspect of the present invention, the positive
displacement pump is a
diaphragm pump and the first inlet fitting further includes a check valve
configured to prevent
backflow of the mixed solution toward the first tank.
[0010] In still another aspect of the present invention, the mixing
manifold further includes
a disc defining a first annular series of spaced-apart flow-metering holes.
Successive respective
flow-metering holes have an increasing hole diameter and the disc is adapted
to rotate to align a
selected flow-metering hole in fluid communication with the second inlet to
thereby define the
selectively adjustable amount of concentrate in the mixed solution. The disc
may further define a
second annular series of spaced-apart stop holes. Each respective stop hole
within the second
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annular series radially aligns with a respective flow-metering hole of the
first annular series. A
single respective stop hole receives a stop member when the selected flow-
metering hole is aligned
with the second inlet. The stop member may be a ball bearing biased to engage
the disc wherein a
diameter of the ball bearing is slightly larger than a diameter of each of the
stop holes.
[0011] In another aspect of the present invention, the first inlet
fitting may further include a
check valve configured to prevent backflow of the mixed solution toward the
first tank and the
second tank may be removably mounted to the mounting bracket on the first
tank.
[0012] In still a further aspect of the present invention, the second
tank may include a quick
disconnect coupling configured to releasably couple a concentrate tube to a
tank fitment defined on
the second tank. The concentrate tube may then deliver the liquid concentrate
to the mixing
manifold. The quick disconnect coupling may comprise a fitment housing having
a first end, a
second end and a stepped bore region therebetween, wherein the first end is
coupled to the tank
fitment defined on the second tank. A tubing nut may be removably coupled to
the second end of
the fitment housing and a tubing coupling may be configured to be received
within the tubing nut
and abut against a mouth opening defined by the second end of the fitment
housing. A plug
member may have a plug end, a flanged end and a body portion therebetween. The
plug end may
be received in the first end of the fitment housing while the flanged end may
be received within the
second end of the fitment housing and the body portion may extend through the
stepped bore
region of the fitment housing. A biasing member may also be received within
the stepped bore
region, wherein the biasing member urges the plug end of the tubing coupling
to seal the first end
of the fitment housing when the tubing nut is removed from the second end of
the fitment housing.
A biasing force is stored within the biasing member by the flanged end when
the tubing nut is
coupled to the second end of the fitting housing, whereby fluid concentrate
within the second tank
can flow through the quick disconnect coupling to the mixing manifold. The
body portion of the
plug member may comprise a plurality of spaced apart spindles with open slots
defined
therebetween to permit flow of fluid concentrate therethrough.
[0013] In yet another aspect of the present invention, the sprayer system
may further
include a pressure by-pass recirculation loop fluidly coupling the pressure
port to the suction port.
The pressure by-pass recirculation loop may be configured to selectively
regulate a fluid pressure
of the mixed solution being delivered to the spray device. The pressure by-
pass recirculation loop
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may be either internal to the positive displacement pump or an external
pathway around the
positive displacement pump.
[0014] In accordance with another aspect of the present invention, the
present invention is
generally directed to a sprayer system comprising a first tank configured to
hold a diluent; a
mounting bracket mounted to the first tank; and a second tank removably
mounted to the first tank
and configured to hold a liquid concentrate. A mixing manifold is mounted to
the mounting
bracket and has a first inlet fitting configured to receive a fixed amount of
diluent from the first
tank and a second inlet configured to receive a selectively adjustable amount
of liquid concentrate
from the second tank. The fixed amount of diluent and selectively adjustable
amount of
concentrate are combined to form a mixed solution. The mixing manifold
includes a mixed
solution outlet and a positive displacement pump is mounted to the mounting
bracket and has a
suction port fluidly coupled to the mixed solution outlet. A pressure port may
be fluidly coupled to
at least one spray device. The second tank may be separable from the first
tank without requiring
removal of the mixing manifold or positive displacement pump. The at least one
spray device may
be a low pressure spray nozzle or a high pressure boom carrying two or more
boom nozzles.
Alternatively, the at least one spray device is a low pressure spray nozzle
and a high pressure boom
carrying two or more boom nozzles whereby the mixed fluid is selectively
received by either the
low pressure spray nozzle or the high pressure boom. The sprayer system may
further include a
pressure by-pass recirculation loop fluidly coupling the pressure port to the
suction port. The
pressure by-pass recirculation loop may be configured to selectively regulate
a fluid pressure of the
mixed solution being received by the low pressure spray nozzle. The pressure
by-pass recirculation
loop may be either internal to the positive displacement pump or an external
pathway around the
positive displacement pump.
[0015] In view of the above and in accordance with an aspect of the
present invention, the
present invention is generally directed to a backpack sprayer system including
a mounting bracket
having a battery receiving fixture to receive a battery therein. A first tank
is mounted to the
mounting bracket and holds a diluent. A second tank is mounted to the mounting
bracket and holds
a liquid concentrate. A mixing manifold is mounted to the mounting bracket and
has a first inlet
fitting to receive a fixed amount of diluent from the first tank and a second
inlet to receive an
adjustable amount of liquid concentrate from the second tank. The fixed amount
of diluent and
adjustable amount of concentrate are combined to form a mixed solution and the
mixing manifold
CA 304.0672 2019-04-18
includes a mixed solution outlet. A positive displacement pump is mounted to
the mounting
bracket and a suction port coupled to the mixed solution outlet and a pressure
port fluidly coupled
with a spray device. A control unit is mounted on the mounting bracket and
receives power from
the battery. The positive displacement pump may be a diaphragm pump. The first
inlet fitting may
also include a check valve configured to prevent backflow of the mixed
solution toward the first
tank.
[0016] In a further aspect of the present invention, the mixing manifold
further includes a
disc defining a first annular series of spaced-apart flow-metering holes.
Successive respective
flow-metering holes have an increasing hole diameter and the disc is adapted
to rotate to align a
selected flow-metering hole of the annular series of spaced-apart holes in
fluid communication with
the second inlet to thereby define the selectively adjustable amount of
concentrate in the mixed
solution. The disc may further define a second annular series of spaced-apart
stop holes. Each
respective stop hole within the second annular series radially aligns with a
respective flow-
metering hole of the first annular series. A single respective stop hole
receives a stop member
when the selected flow-metering hole is aligned with the second inlet. The
stop member may be a
ball bearing biased to engage the disc, wherein a diameter of the ball bearing
is slightly larger than
a diameter of each of the stop holes.
[0017] In still another aspect of the present invention, a battery may be
removably secured
within the battery receiving fixture. The battery is operably coupled to the
positive displacement
pump and control unit whereby the battery is configured to provide power to
the positive
displacement pump and control unit when the sprayer system is in an on
configuration.
[0018] In another aspect of the present invention, the second tank is
fixedly secured within
the first tank, whereby an open volume defined by the second tank is fluidly
isolated from an open
volume defined by the first tank. The second tank may also include a
concentrate fitting
configured to receive a first end of a concentrate tube. The second end of the
concentrate tube is
coupled to the second inlet of the mixing manifold. The first tank may also
include a diluent fitting
configured to receive a first end of a diluent tube. The second end of the
diluent tube is coupled to
the first inlet of the mixing manifold. The second tank may further include a
liquid level gauge.
[0019] In still a further aspect of the present invention, the control
unit comprises a printed
circuit board and a control panel interface. The printed circuit board
includes a processor and a
memory, wherein the processor is configured to perform one or more functions
including power
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on/power off, regulating power to the positive displacement pump so as to vary
output pressure of
the mixed solution, monitoring and displaying a battery charge level, and
indicating pacing. The
control panel interface is coupled to the printed circuit board and includes
one or more control
buttons whereby a user may selectively control the processor functions.
[0020] Additional objects, advantages and novel aspects of the present
invention will be set
forth in part in the description which follows, and will in part become
apparent to those in the
practice of the invention, when considered with the attached figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a perspective view of a sprayer system in accordance
with an aspect of the
present invention;
[0022] FIG. 2 is an exploded view of the sprayer system shown in FIG. 1;
[0023] FIG. 3 is a front perspective view of the sprayer system shown in
FIG. 1 with the
diluent tank removed;
[0024] FIG. 4 is a rear perspective view of the sprayer system shown in
FIG. 3;
[0025] FIG. 5 is an exploded view of a liquid concentrate tank used
within the sprayer
system shown in FIG. 1;
[0026] FIG. 6 is a cross section view of the liquid concentrate tank used
within the sprayer
system shown in FIG. 1;
[0027] FIG. 7 is a cross section view of a tubing fixture used with the
liquid concentrate
tank shown in FIG. 5;
[0028] FIG. 8 is an exploded cross section view of the tubing fixture
shown in FIG. 7;
[0029] FIG. 9 is a top perspective view of a mixing manifold used within
the sprayer
system shown in FIG. 1;
[0030] FIG. 10 is a bottom perspective view of the mixing manifold shown
in FIG. 9;
[0031] FIG. 11 is a top front exploded view of the mixing manifold shown
in FIGS. 9 and
10;
[0032] FIG. 12 is a bottom front exploded view of the mixing manifold
shown in FIGS. 9
and 10;
[0033] FIG. 13 is a cross section view of the mixing manifold, taken
generally along line
13-13 in FIG. 9;
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[0034] FIG. 14 is an isolated view of a disc used within the mixing
manifold shown in
FIGS. 9 through 13;
[0035] FIG. 15 is a schematic view of a pressure by-pass system suitable
for use within a
variable pressure sprayer system in accordance with an aspect of the present
invention;
[0036] FIG. 16 is a front perspective view of a sprayer system in
accordance with an aspect
of the present invention;
[0037] FIG. 17 is a rear perspective view of the sprayer system shown in
FIG. 16;
[0038] FIG. 18 is a bottom front perspective view of the sprayer system
shown in FIG. 16;
[0039] FIG. 19 is a front elevational view of the sprayer system shown in
FIG. 16;
[0040] FIG. 20 is a cross section view of the sprayer system, taken
generally along line 20-
20 in FIG. 19;
[0041] FIG. 21 is a bottom plan view of the sprayer system shown in FIG.
16;
[0042] FIG. 22 is a longitudinal cross section view the sprayer system
shown in FIG. 19;
[0043] FIG. 23 is top plan view of the sprayer system shown in FIG. 16;
[0044] FIG. 24 is an exploded view of the sprayer system shown in FIG.
16; and
[0045] FIG. 25 is a plan view of a control panel interface configured for
use with the
sprayer system shown in FIG. 16.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] Referring now to FIGS. 1 and 2, in accordance with an aspect of
the present
invention, sprayer system 10 may generally comprise a first tank 12, mounting
bracket 14, second
tank 16, mixing manifold 38 and positive displacement pump 42, such as and
without limitation
thereto, a diaphragm pump. Mounting bracket 14 may be mounted to first tank
12, such as via
mechanical fasteners 18. To provide further support and to resist lateral
movement of mounting
bracket 14 in the x-z plane, first tank 12 may include a tang 20 configured to
reside within a notch
22 defined within mounting bracket 14. Second tank 16 may be mounted to first
tank 12 and
mounting bracket 14, such as via a strap (not shown). To that end, second tank
16 may include a
strap recess 24 configured to receive the strap and first tank 12 may further
include a strap tie down
clamp 26 whereby movement of second tank 16 in the y-axis is prohibited. To
minimize lateral
displacement of second tank 16 (i.e., in the x-z plane) mounting bracket 14
may include one or
more upwardly extending nodules 28 configured to coincide with matching
indentations 30 defined
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on bottom wall 32 of second tank 16 (see FIG. 6). In this manner, a user may
unfasten the strap
and lift second tank away from mounting bracket 14 and first tank 12, such as
via handle 17,
without requiring the use of tools. Strap tie down clamp 26 may further
include a wand receiving
portion 34 defining a wand receiving recess 36 whereby a spray wand (not
shown) may be
releasably coupled to sprayer system 10 when the spray wand is not in use.
With continued
reference to FIGS. 1 and 2, and with additional reference to FIGS. 3 and 4, a
mixing manifold 38
may be mounted to mounting bracket 14, such as via mechanical fasteners 40,
and positive
displacement pump 42 may be mounted to mounting bracket 14 such as via
mechanical fasteners
44. In this manner, each of the second tank 16, mixing manifold 38 and
positive displacement
pump 42 may be individually and separately removed from mounting bracket 14
and first tank 12.
[0047] In operation, first tank 12 includes a diluent outlet 46 having a
diluent fitting 47
configured to receive one end of diluent tubing (not shown) in a substantially
fluid-tight seal. The
opposing end of the diluent tubing is mounted onto a first inlet fitting 48 of
mixing manifold 38
(see also FIGS. 9-13). First inlet fitting 48 may include a tapered nipple 50
and ribbed portion 52
so as to snuggly receive the diluent tubing thereon in a substantially fluid-
tight seal. An optional
hose clamp (not shown) may also be used to more securely clamp the diluent
tubing to ribbed
portion 52. Mixing manifold 38 may further include a second inlet 54
configured to receive
concentrate tubing (not shown) from second tank 16. As shown most clearly in
FIGS. 4 and 10,
mixing manifold 38 may include a notch 56 proportioned to permit passage of
concentrate tubing
through housing 58 of mixing manifold 38. Mounting bracket 14 may also include
a recess 60 to
accommodate passage of the concentrate tubing (see FIGS. 2 and 4). Thus, a
first end of the
concentrate tubing may be mounted to fitment 62 housed within second inlet 54.
The concentrate
tubing may then extend toward second tank 16 wherein the opposing end of the
concentrate tubing
is mounted to second tank 16 via concentrate outlet fitting 64.
[0048] With reference to FIGS. 5 and 6, second tank 16 may be filled with
a selected fluid
concentrate through tank opening 19 defined by a threaded mouth portion 21. A
cap 23 may be
removably threaded onto mouth portion 21 so as to seal second tank 16. An
optional 0-ring 25
may also facilitate a fluid-tight seal between second tank 16 and cap 23. To
prevent clogging of
downstream plumbing components, mouth portion 21 may further receive filter
element 27 therein.
When filling second tank 16 with fluid concentrate, the fluid will pass
through filter element 27
whereby particulate matter larger than the pore size of the filter element
will be strained out of the
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1
fluid. Accordingly, the pore size of filter element 27 should be selected so
as to be smaller than the
internal diameter of the smallest diameter downstream component, such as disc
168 which will be
discussed in greater detail below.
[0049] With reference to FIGS. 7 and 8, to facilitate tool-less removal
of second tank 16
from mounting bracket 16 and mixing manifold 38, concentrate outlet fitting 64
may be a quick
disconnect coupling generally comprised of a fitment housing 66 having a first
end 68 configured
to be threadably coupled to a corresponding tank fitment 70 defined on second
tank 16 (see FIG.
5). First end 68 of fitment housing 66 may also be configured to receive a
tank tubing coupling 72
whereby tank tubing coupling 72 includes a flanged end 74 proportioned to abut
against mouth
opening 76 of tank fitment 70 such that tank tubing coupling 72 is entrapped
between mouth
opening 76 and stepped wall 78 of fitment housing 66 when fitment housing 66
is threaded onto
tank fitment 70. To promote a fluid-tight seal between tank fitment 70 and
fitment housing 66, one
or more seals, such as 0-rings 80, 82 may be included. The opposing end of
tank tubing coupling
72 may include one or more barbs 84 dimensioned to snuggly receive a
concentrate pick-up tube
(not shown) which may extend from tank tubing coupling 72 to proximate bottom
wall 32 of
second tank 16. In this manner, liquid concentrate may be drawn from second
tank 16 as will be
described in greater detail below.
[0050] With continued reference to FIGS. 7 and 8, second end 86 of
fitment housing 66
may include male threads 88 configured to threadably engage female threads 90
defined within a
first end 92 of tubing nut 94. Second end 86 may further define a bore 96
dimensioned to receive a
first end 98 of a concentrate tubing coupling 100 therein upon threaded
engagement of tubing nut
94 with fitment housing 66. The opposing end 102 of concentrate tubing
coupling 100 may include
one or more barbs 104 dimensioned to snuggly receive the opposing end of the
concentrate tubing
as described above. Annular flange 106 on concentrate tubing coupling may
engage seat portion
95 of tubing nut 94 such that tubing nut 94 may permit mounting of concentrate
tubing coupling
100 to second tank 16 with minimal, if any, twisting of the concentrate tubing
as tubing nut 94 is
rotatably threaded onto male threads 88. To assist in properly seating
concentrate tubing coupling
100 within fitment housing 66, annular flange 106 may also be dimensioned to
abut against the
mouth opening 110 of bore 96 when tubing nut 94 is fully tightened. An 0-ring
seal 112 may also
promote a fluid-tight seal between concentrate tubing coupling 100 and bore 96
of fitment housing
66.
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[0051] In a further aspect of the invention, bore 96 may be further
include a series of steps
114, 116, 118 thereby defining bore regions 96a, 114a, 116a, 118a. Concentrate
tubing coupling
100 may reside within bore region 96a such that terminal end 120 of first end
98 of concentrate
tubing coupling 100 may seat against step 114. The wall thickness of terminal
end 120 may be
selected so that internal bore 122 of concentrate tubing coupling 100 is
slightly smaller than the
diameter of bore region 114a. In this manner, terminal end 120 partially
occludes bore region 114a
whereby flanged end 124 of plug member 126 may be engaged by concentrate
tubing coupling 100
as tubing nut 94 is threaded onto fitment housing 66. Bore region 114a may be
proportioned to
receive flanged end 124 while step 116 has a smaller diameter than flanged end
124 whereby
flanged end 124 is precluded from entering bore region 116a. Plug member 126
may further
include a body portion 128 dimensioned to pass through and extend within bore
regions 116a, 118a
before terminating at a second end 130. Second end 130 of plug member 126 may
include an 0-
ring seal 132 having an external diameter greater that the diameter of bore
region 118a. In one
aspect of the invention, body portion 128 may be comprised of a plurality of
spaced-apart spindles
134 configured to define open slots 136 therebetween so as to promote fluid
travel through plug
member 126, as will be discussed in greater detail below.
[0052] Plug member 126 may translate along longitudinal axis L of fitment
housing 66 so
as to selectively plug or unplug bore region 118a and control outflow of
liquid concentrate from
second tank 16 to mixing matrix 38. To that end, as shown in FIG. 7, tubing
nut 94 may be
threadably coupled to fitment housing 66 to thereby secure concentrate tubing
coupling 100
therein. Terminal end 120 of concentrate tubing coupling 100 engages flanged
end 124 of plug
member 126 so as to direct second end 130 a spaced distance from bore region
118a. In this
position, fluid may flow from second tank 16 through tank tubing coupling 72,
fitment housing 66
and the concentrate tubing coupling before passing to mixing manifold 38.
[0053] Fitment housing 66 may further include a biasing member, such as
compression
spring 138, configured to engage flanged end 124 at a first end 140 and step
118 at second end 142.
In this manner, threading of tubing nut 94 and concentrate tubing coupling 100
may compress
spring 138 to thereby cause potential energy to be stored within spring 138.
Unthreading of tubing
nut 94 and removal of concentrate tubing coupling 100 from fitment housing 66
enables spring 138
to release the stored potential energy so as to cause plug member 126 to
translate along longitudinal
axis L generally in the direction generally indicated by arrow 144. Plug
member 126 will continue
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to translate until 0-ring 132 engages surface 146 of fitment housing 66
whereby 0-ring 132 and
second end 130 of plug member 126 occlude bore region 118a. In this manner,
fluid concentrate
may no longer flow into concentrate tubing coupling 100. As a result, second
tank 16 may be
rendered substantially leak proof. Second tank 16 may then be removed from
mounting bracket 14
as described above and stored with minimal to no loss of liquid concentrate.
100541 In accordance with an aspect of the invention, following removal
of second tank 16
as described above, a replacement second tank (not shown) may be mounted to
mounting bracket
14. Tubing nut 94 and concentrate tubing coupling 100 may then be threaded
onto a fitment
housing (similar to fitment housing 66) on the replacement second tank as
described above. As a
result, the plug member within the fitment housing may be opened so as to
allow transfer of the
alternative liquid concentrate within the replacement second tank to mixing
manifold 38 as
described above. In a further aspect of the invention, a replacement second
tank may be filled with
water so as to enable flushing of the system between chemicals that are to be
sprayed, thereby
reducing cross-contamination or misapplication of the chemicals. Thus, sprayer
system 10 may be
configured to selectively spray any number of various liquid concentrates
requiring only the
removal and replacement of selected second tanks and remounting of tubing nut
94 and concentrate
tubing coupling 100. Respective second tanks may be stored with little to no
threat of leakage of
respective liquid concentrates contained therein, thereby reducing waste of
the concentrates.
Moreover, user exposure to a concentrate is minimized as the second tank does
not need to be
emptied, washed and refilled every time a new liquid concentrate desired to be
sprayed.
[0055] Turning now to FIGS. 9-13, various views of mixing manifold 38 are
shown. As
can be seen, housing 58 of mixing manifold 38 may be generally comprised of
upper 148 and lower
150 housing subunits. Manifold support member 152 may be interposed between
subunits 148,
150. To that end, the interior corners of lower housing subunit 150 may
include nodules 154
dimensioned such that respective feet 156 on manifold support member 152 seat
upon respective
nodules 154. Upper housing subunit 148 may include respective lobes 158
dimensioned to receive
a respective foot 156 therein. Each lobe 158 may also include a notch 160 for
permitting passage
therethrough of a respective leg 162 on manifold support member 152. In this
manner, manifold
support member 152 may be securely seated within manifold housing 58 and be
constrained so as
to prevent lateral and torsional movement of manifold support member 152. As
described above,
manifold support member 152 includes second inlet 54 configured to receive
fitment 62. Manifold
12
CA 304.0672 2019-04-18
support member 152 may further include a spring well 164 dimensioned to
receive a stop spring
166, as will discussed in greater detail below.
10056] Mixing manifold 38 may further include disc 168 rotatably mounted
atop manifold
support member 152 whereby center hole 170 defined by disc 168 receives post
172 formed on
manifold support member 152. Disc 168 may then be capped by upper housing
subunit 148
wherein upper housing subunit 148 includes one or more openings 174
therethrough such that a
portion of the outer circumference of disc 168 may be engaged by a user so as
to selectively rotate
disc 168 about post 172. With additional reference to FIG. 14, disc 168 may
further define an outer
annular series of spaced-apart through-holes, such as flow metering holes 176a-
176h. Each of flow
metering holes 176a-176h may have a slightly larger diameter than the
immediately preceding flow
metering hole. In operation one of holes 176a-176h is aligned with internal
bore 178 defined by
fitment 62. Fitment spring 63 may urge fitment 62 against disc 168 so as to
create and maintain a
substantially fluid-tight seal between fitment 62 and disc 168. In this
manner, a user may
selectively control the volume of liquid concentrate that may pass through
disc 168, as will be
discussed in greater detail below.
[0057] Disc 168 may also further define an inner annular series of spaced
apart through-
holes, such as chamfered spring stop holes 180a-180h. Each respective spring
stop hole 180a-180h
is configured to align radially with its respective flow metering hole 176a-
176h. In operation, a
selected one of holes 180a-180h is aligned with spring well 164 whereby a
positive stop member,
such as ball bearing 182, seats within a portion of the selected spring stop
hole 180a-180h through
urging of stop spring 166 resident within spring well 164. In this manner, a
user may receive
feedback indicating proper alignment of the selected flow metering hole 176a-
176h upon seating of
ball bearing 182. To change the amount of liquid concentrate added to the
diluent stream, a user
may rotate disc 168 whereby disc 168 may apply downward force against ball
bearing 182 so as to
compress stop spring 166 within spring well 164. Disc 168 may then be further
rotated until the
desired flow metering hole 176a-176h is aligned with internal bore 178 of
fitment 62 such that ball
bearing 182 seats within the desired spring stop hole 180a-180h. As most
clearly shown in FIG.
14, disc 168 may also include respective indicia 184a-184h proximate a
respective flow metering
hole 176a-176h. Indicia 184a-184h may correlate with the respective diameter
of respective flow
metering holes 176a-176h so as to provide visual indication to the user as to
which of the
respective flow metering holes 176a-176h is currently aligned with internal
bore 178 of fitment 62.
13
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1
[0058] As seen most clearly in FIG. 13, mixing manifold 38 may include a
fluid channel
186 wherein a first end 188 of fluid channel 186 may define female threads 190
configured to
matingly receive corresponding male threads 192 defined by manifold terminus
194 of first inlet
fitting 48. The opposing second end 196 of fluid channel 186 may similarly
define female threads
198 configured to matingly receive corresponding male threads 200 on manifold
terminus 202 of
manifold outlet fitting 204. A flow plug 206 may be interposed within fluid
channel 186 adjacent
the internal extent of female threads 190. Fluid channel 186 may further
define a step 208 so as to
provide a positive stop to insertion of flow plug 206 in the direction
generally indicated by arrow
210. In this manner, bore 212 of first inlet fitting 48 may align with the
longitudinal axis P of
longitudinal bore 214 of flow plug 206 whereby a constant volume of diluent
may be received from
first tank 12 after flowing through first inlet fitting 48 into flow plug 206.
[0059] As further seen in FIG. 13, flow plug 206 may further include a
radially extending
bore 216 which may be configured to fluidly align with one of flow metering
holes 176a-176h and
internal bore 178 of fitment 62. In this manner, a user selected volume of
liquid concentrate may
be received from second tank 16, wherein the selected volume of liquid
concentrate is then mixed
with, and diluted by, the constant volume of diluent being received through
first inlet 48 as
described above. Flow plug 206 may also define an annular groove 218
configured to define a
fluid tight channel with internal wall surface 220 of mixing manifold 38.
Annular groove 218
coincides with radially extending bore 216 such that fluid concentrate may
still pass through
radially extending bore 216 into longitudinal bore 214 should radially
extending bore 216 be
misaligned with one of flow metering holes 176a-176h and internal bore 178.
Fluid channel 186
may further define a mixing chamber portion 222 which may further promote
mixing of the diluent
and fluid concentrate prior to outputting the mixed fluid through manifold
outlet fitting 204.
[0060] With reference to FIGS. 3 and 4, manifold outlet tubing (not
shown) may fluidly
couple manifold outlet fitting 204 with positive displacement pump suction
port 224. In this
manner, upon a suction stroke of positive displacement pump 42, mixed fluid is
drawn into pump
42 from mixing manifold 38. As described above, the mixed fluid is comprised
of a constant
volume of diluent into which is charged a user-selected volume of liquid
concentrate. Thus, on a
pressure stroke of pump 42, the mixed fluid is forced out of pressure port 226
of positive
displacement pump 42. Pressure port 226 may be fluidly coupled to a spray
device, such as a spray
wand or boom sprayer (not shown). To prevent backflow of mixed fluid through
first inlet fitting
14
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48 into first tank 12, first inlet fitting 48 may include a check valve 228
(see FIG. 13). In this
manner, cyclical operation of positive displacement pump 42 will alternately
draw mixed fluid
from mixing manifold 38 and discharge this mixed fluid through an attached
sprayer whereby the
concentration of the fluid concentrate dilution is selected, and easily
modified by, the user through
setting of disc 168. In should be understood by those skilled in the art that
positive displacement
pump 42 may be powered by any suitable power source, such as a dedicated
battery or through
wiring pump 42 to the battery of the vehicle (e.g., ATV or golf cart).
[0061] Turning now to FIG. 15, a sprayer system 10' may be configured to
operate as a
variable pressure sprayer. Sprayer system 10' may include first tank 12 and
second tank 16 each
fluidly coupled to mixing manifold 38 as described above with regard to
sprayer system 10. Check
valve 228 may be interposed between mixing manifold 38 and first tank 12 to
prevent backflow of
mixed fluid into first tank 12, also as described above. Mixed fluid may be
drawn from mixing
manifold 38 through operation of positive displacement pump 42 whereby the
mixed fluid is output
through pressure port 226. The mixed fluid may then be selectively delivered
to a spray nozzle 230
(such as a handheld sprayer) or to a boom 232 upon which are mounted a
plurality of boom nozzles
234.
[0062] In accordance with one aspect of the invention, flow to spray
nozzle 230 or boom
232 may be selectively controlled by a selector valve 236. Flow control at
each boom nozzle 234
may also be further controlled by respective ball valve 238. Spray nozzle 230
may also include a
pressure reducing valve 240 which is metered to control the fluid pressure of
the mixed fluid
entering spray nozzle 230 so as to minimize or prevent damage to spray nozzle
230.
[0063] Positive displacement pump 42 may include a pressure by-pass
recirculation loop
242 fluidly coupling pressure port 226 with suction port 224. Pressure by-pass
recirculation loop
242 may operate to decrease the fluid pressure of the mixed fluid being
delivered to spray nozzle
230 while also maintaining segregation of the mixed fluid from either first
tank 12 or second tank
16. Pressure by-pass recirculation loop 242 may be either internal to positive
displacement pump
42 of may be en external pressure by-pass loop around positive displacement
pump 42.
[0064] Referring now to FIGS. 16 through 24, in accordance with a further
aspect of the
present invention, a backpack sprayer system 300 may generally comprise a
first tank 312 and
second tank 316 mounted onto a mounting bracket 314. Backpack sprayer system
300 may further
CA 3040672 2019-04-18
1
include a mixing manifold 38 and positive displacement pump 42, such as those
described above
with regard to spray system 10.
[0065] As shown most clearly in FIGS. 16-19, 22, 24, mounting bracket 314
include a
mounting plate 318 and extended upper sidewall portion 320. In this manner,
mounting bracket
314 may receive first tank 312 within upper sidewall portion 320 whereby
bottom wall 312a of first
tank 312 sits upon mounting plate 318. As further shown in FIGS. 22 and 24,
second tank 316 may
be defined by a sidewall 322 and bottom wall 324. In one aspect, second tank
316 may reside
within, and be fixedly secured to, first tank 312, although it should be noted
that in other
embodiments, second tank 316 may be separable from first tank 312. Rear wall
312b of first tank
312 and rear wall 314b of mounting bracket 314 may have a curved profile so as
to more
ergonomically rest against a user's back during use. To secure backpack
sprayer system 310 to the
user's back, sides 314c, 314d of mounting bracket 314 may include a strap clip
326. In this
manner, first ends of respective straps (not shown) may be secured to a
respective strap clip 326.
The opposing second end of each strap may then be secured to tank clip 328
mounted on top wall
312c of first tank 312. The straps may be worn over the user's shoulders so as
to hold backpack
sprayer system 310 against the back of the user.
[0066] With continued reference to FIGS. 16-19, 22, 24, and with
additional reference to
FIG. 20, mounting plate 318 may define a pair of orifices 330, 332 therein.
Orifice 330 may be
proportioned to allow passage of first tank fitting 334 therethrough, while
orifice 332 is
proportioned to allow passage of second tank fitting 336 therethrough. A
mixing manifold 38 may
be mounted to mounting bracket 314 and include a first inlet fitting 48 and
second inlet fitting 54.
Diluent tubing 338 may fluidly couple first tank fitting 334 with first inlet
fitting 48 while
concentrate tubing 340 may fluidly couple second tank fitting 336 with second
inlet fitting 54. In
this manner, mixing manifold 38 may receive a fixed amount of diluent from the
first tank and an
adjustable amount of liquid concentrate from the second tank. The fixed amount
of diluent and
adjustable amount of concentrate are then combined within mixing manifold 38
to form a mixed
solution which is discharge from mixing manifold 38 through a mixed solution
outlet, such as
manifold outlet fitting 204 (FIG. 24).
[0067] As described above, manifold outlet tubing, such as tubing 342,
may fluidly couple
manifold outlet fitting 204 with positive displacement pump suction port 224.
In this manner, upon
a suction stroke of positive displacement pump 42, mixed fluid is drawn into
pump 42 from mixing
16
CA 3040672 2019-04-18
manifold 38. The mixed fluid is comprised of a constant volume of diluent into
which is charged a
user-selected volume of liquid concentrate. Thus, on a pressure stroke of pump
42, the mixed fluid
is forced out of pressure port 226 of positive displacement pump 42 (FIG. 21).
Pressure port 226
may be fluidly coupled to a spray device, such as a spray wand (not shown),
accessible through
hole 344 defined in front wall 314a of mounting bracket 314 (FIGS. 16, 18 and
19)
[0068] As described above with reference to FIGS. 9-13, housing 58 of
mixing manifold 38
may be generally comprised of upper 148 and lower 150 housing subunits.
Manifold support
member 152 may be interposed between subunits 148, 150. To that end, the
interior corners of
lower housing subunit 150 may include nodules 154 dimensioned such that
respective feet 156 on
manifold support member 152 seat upon respective nodules 154. Upper housing
subunit 148 may
include respective lobes 158 dimensioned to receive a respective foot 156
therein. Each lobe 158
may also include a notch 160 for permitting passage therethrough of a
respective leg 162 on
manifold support member 152. In this manner, manifold support member 152 may
be securely
seated within manifold housing 58 and be constrained so as to prevent lateral
and torsional
movement of manifold support member 152. As described above, manifold support
member 152
includes second inlet 54 configured to receive fitment 62. Manifold support
member 152 may
further include a spring well 164 dimensioned to receive a stop spring 166, as
will discussed in
greater detail below.
[0069] Mixing manifold 38 may further include disc 168 rotatably mounted
atop manifold
support member 152 whereby center hole 170 defined by disc 168 receives post
172 formed on
manifold support member 152. Disc 168 may then be capped by upper housing
subunit 148
wherein upper housing subunit 148 includes one or more openings 174
therethrough such that a
portion of the outer circumference of disc 168 may be engaged by a user so as
to selectively rotate
disc 168 about post 172. With additional reference to FIG. 14, disc 168 may
further define an outer
annular series of spaced-apart through-holes, such as flow metering holes 176a-
176h. Each of flow
metering holes 176a-176h may have a slightly larger diameter than the
immediately preceding flow
metering hole. In operation one of holes 176a-176h is aligned with internal
bore 178 defined by
fitment 62. Fitment spring 63 may urge fitment 62 against disc 168 so as to
create and maintain a
substantially fluid-tight seal between fitment 62 and disc 168. In this
manner, a user may
selectively control the volume of liquid concentrate that may pass through
disc 168, as will be
discussed in greater detail below.
17
CA 3040672 2019-04-18
[0070] Disc 168 may also further define an inner annular series of spaced
apart through-
holes, such as chamfered spring stop holes 180a-180h. Each respective spring
stop hole 180a-180h
is configured to align radially with its respective flow metering hole 176a-
176h. In operation, a
selected one of holes 180a-180h is aligned with spring well 164 whereby a
positive stop member,
such as ball bearing 182, seats within a portion of the selected spring stop
hole 180a-180h through
urging of stop spring 166 resident within spring well 164. In this manner, a
user may receive
feedback indicating proper alignment of the selected flow metering hole 176a-
176h upon seating of
ball bearing 182. To change the amount of liquid concentrate added to the
diluent stream, a user
may rotate disc 168 whereby disc 168 may apply downward force against ball
bearing 182 so as to
compress stop spring 166 within spring well 164. Disc 168 may then be further
rotated until the
desired flow metering hole 176a-176h is aligned with internal bore 178 of
fitment 62 such that ball
bearing 182 seats within the desired spring stop hole 180a-180h. As most
clearly shown in FIG.
14, disc 168 may also include respective indicia 184a-184h proximate a
respective flow metering
hole 176a-176h. Indicia 184a-184h may correlate with the respective diameter
of respective flow
metering holes 176a-176h so as to provide visual indication to the user as to
which of the
respective flow metering holes 176a-176h is currently aligned with internal
bore 178 of fitment 62.
With reference to FIG. 17, a portion of disc 168 may extend outwardly through
sidewall 314d such
that a user may conveniently adjust the dilution factor of the fluid
concentrate comprising the
mixed fluid.
[0071] As seen most clearly in FIG. 13, mixing manifold 38 may include a
fluid channel
186 wherein a first end 188 of fluid channel 186 may define female threads 190
configured to
matingly receive corresponding male threads 192 defined by manifold terminus
194 of first inlet
fitting 48. The opposing second end 196 of fluid channel 186 may similarly
define female threads
198 configured to matingly receive corresponding male threads 200 on manifold
terminus 202 of
manifold outlet fitting 204. A flow plug 206 may be interposed within fluid
channel 186 adjacent
the internal extent of female threads 190. Fluid channel 186 may further
define a step 208 so as to
provide a positive stop to insertion of flow plug 206 in the direction
generally indicated by arrow
210. In this manner, bore 212 of first inlet fitting 48 may align with the
longitudinal axis P of
longitudinal bore 214 of flow plug 206 whereby a constant volume of diluent
may be received from
first tank 312 after flowing through first inlet fitting 48 into flow plug
206.
18
CA 3040672 2019-04-18
[0072] As further seen in FIG. 13, flow plug 206 may further include a
radially extending
bore 216 which may be configured to fluidly align with one of flow metering
holes 176a-176h and
internal bore 178 of fitment 62. In this manner, a user selected volume of
liquid concentrate may
be received from second tank 316, wherein the selected volume of liquid
concentrate is then mixed
with, and diluted by, the constant volume of diluent being received through
first inlet 48 as
described above. Flow plug 206 may also define an annular groove 218
configured to define a
fluid tight channel with internal wall surface 220 of mixing manifold 38.
Annular groove 218
coincides with radially extending bore 216 such that fluid concentrate may
still pass through
radially extending bore 216 into longitudinal bore 214 should radially
extending bore 216 be
misaligned with one of flow metering holes 176a-176h and internal bore 178.
Fluid channel 186
may further define a mixing chamber portion 222 which may further promote
mixing of the diluent
and fluid concentrate prior to outputting the mixed fluid through manifold
outlet fitting 204.
[0073] With reference to FIGS. 22 and 24, first tank 312 may be filled
with diluent through
tank opening 346 defined by a threaded mouth portion 348. A cap 350 may be
removably threaded
onto mouth portion 348 so as to seal first tank 312. To prevent clogging of
downstream plumbing
components, mouth portion 348 may further receive filter element 352 therein.
When filling first
tank 312, the diluent passes through filter element 352 whereby particulate
matter larger than the
pore size of the filter element will be strained out of the fluid.
Accordingly, the pore size of filter
element 352 should be selected so as to be smaller than the internal diameter
of the smallest
diameter downstream component. Similarly, second tank 316 is configured to
receive fluid
concentrate through mouth portion 354 which is capped by a cap 356. Cap 356
may also carry a
fluid level gauge 358, such as but not limited to a float gauge, an ultrasonic
level gauge and the
like. Cap 356 may also include a dial or meter 360 coupled to gauge 358 so as
to provide a visual
indication of the fluid volume of the fluid concentrate within second tank
316.
[0074] As shown in FIGS. 16, 18 and 24, backpack sprayer system 300 may
include a
battery 362 configured to provide electrical power to positive displacement
pump 42. To that end,
front wall 314a of mounting bracket 314 may include a battery receiving
fixture 364 configured to
removably secure battery 362 within mounting bracket 314. In accordance with
an aspect of the
present invention, battery 362 is a rechargeable, long-life battery, such as a
lithium ion battery.
Mounting bracket 314 may also include a control unit 366 mounted thereon.
Control unit 366 may
comprise a printed circuit board (PCB) 368 and control panel interface 370.
PCB 368 may include
19
CA 3040672 2019-04-18
a processor and memory configured to perform one or more functions including
power on/power
off, regulating power to the positive displacement pump so as to vary output
pressure of the mixed
solution, monitoring and displaying a battery charge level, and indicating
pacing, as described more
fully below. Control panel interface 370 includes one or more control buttons
whereby a user
controls the processor functions of PCB 368.
[0075] As discussed below, control unit 366 may promote smart operation
of backpack
sprayer system 300. With reference to FIG. 25, control panel interface 370 may
generally include a
visual display via output pressure LEDS 370a, battery charge level LEDS 370b,
and a warning
indicator LED 370c and associated buzzer or other audio warning device.
Functionality of the
display, PCB 368 and mechanical components (i.e., positive displacement pump
42) may be
selectively controlled through one or more buttons on control panel interface
370, such as and
without limitation, power/control button 372 and pace button 374.
[0076] By way of example and without limitation thereto, control unit 366
may enable
power on (pressing power/control button 372) and power off (pressing and
holding pace button 374
for a predetermined period of time. Pressure status may be generally indicated
by output pressure
LEDS 370a. For instance, the greater the number of LEDS 370a lit, the higher
the output pressure.
Output pressure may be increased by pressing power/control button 372. When at
maximum
pressure, another press of power/control button 372 will cycle back to the
minimum pressure
setting. Control unit 366 may also permit setting of a set pressure lock
whereby pressing of
power/control button 372 will not cycle the output pressure setting. By way of
example, to set the
pressure lock, PCB 368 may include logic whereby power/control button 372 is
held for a
predetermined period of time (e.g., 10 seconds) at which point the current
pressure setting is
locked, even after backpack sprayer system 300 has turned off or battery 362
has been removed and
replaced. To disable the pressure lock, PCB 368 may include logic, such as,
for example, pressing
power/control button 372 three times followed by pressing pace button 374
within 3 seconds.
[0077] Similarly, pace button 374 may allow cycling of pacing whereby
control unit 366
will emit a beep or other audible signal such that a user may control his or
her walking pace so as
to apply a more consistent spray. Control unit 366 may also keep track of and
indicate total labor
time of backpack sprayer system 300. One exemplary control algorithm to
display total labor time
may include pressing power/control button 372 followed by pressing and holding
power/control
button 372 and pace button 374 simultaneously for a predetermine period of
time. Output pressure
CA 3040672 2019-04-18
LEDS 370a may then blink to indicate a time range, i.e., 0 LEDs indicates less
than 300 hours, 1
LED indicates between 300 and 700 hours, 2 LEDS indicates between 700 and 1000
hours, etc.
Warning indicator LED 370c and associated buzzer may be used to indicate a
problem associated
with the battery, e.g., that the battery has low charge or is experiencing an
overvoltage.
[0078] The foregoing description of the preferred embodiment of the
invention has been
presented for the purpose of illustration and description. It is not intended
to be exhaustive nor is it
intended to limit the invention to the precise form disclosed. It will be
apparent to those skilled in
the art that the disclosed embodiments may be modified in light of the above
teachings. The
embodiments described are chosen to provide an illustration of principles of
the invention and its
practical application to enable thereby one of ordinary skill in the art to
utilize the invention in
various embodiments and with various modifications as are suited to the
particular use
contemplated. Therefore, the foregoing description is to be considered
exemplary, rather than
limiting, and the true scope of the invention is that described in the
following claims.
21
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