Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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METHOD AND APPARATUS FOR TREATMENT OF WATER
The present invention relates to ion-exchange and filter
water systems, and, more particularly, to an ion-exchange resin
bed system.
Ion-exchange water treatment systems may be of two general
types, i.e., a timed system and a demand system. A timed system
utilizes a timer to regenerate a resin bed within a treatment
tank of the water treatnlent system after a particular period of
time has elapsed. with a timed system, it is necessary to
estimate, based upon the users application demand, water usage
history, etc., when the treatment tank should be regenerated. If
actual water usage exceeds the capacity of the unit during the
time period, "untreated" water (i.e., water containing impurities
such as iron, calcium and magnesium) could be output by the water
treatment system. Accor.dingly, timed water treatment systems are
typically regenerated well ahead of the point when the total
amount of normal water use would occur to prevent the occurrence
of such "untreated" water. Such systems have the disadvantage of
discharging excess water and regenerant, e.g., salt, into a sewer
system, with associated detrimental environmental impact.
A demand system of conventional design utilizes a flow meter
(or turbine) at the output valve of the treatment tank to count
the actual amount of water used since the last regeneration. The
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flow meter outputs signals to an electron:%c counter which
initiates regeneration when the pre-set count (corresponding to a
total amount of flow through the treatment tank outlet) equals a
preset amount corresponding to an exchange capacity of the resin
bed within the treatment, tank. However, such systems are limited
by the sensitivity of the flow meter. Such meters are not
typically able to count all the flow therethrough in a small
amount per unit of time, such as caused by drips from sinks,
appliances, etc. Also, such meters are unable to register if an
overlap or overdrive occurred at extremely high flow rates. Such
small amounts of water which actually pass through the flow meter
(or turbine) but which are not detected thereby actually amount
to several gallons per hour, or even more. Because conventional
systems do not allow for such lost water, the system may
experience oversaturation or overrun of capacity after a certain
volume of water. That is, the system continues to operate after
the resin bed is unable to perform additional ion exchange,
resulting in untreated water being output from the water
treatment system.
U.S. Patent No. 4,104,165 (Braswell), assigned to the
assignee of the present invention, discloses a water softening
system which may be regenerated on a timed basis. Braswell
discloses a valve head assembly mounted to a treatment tank and
having a poppet type plunger valve disposed therein. The plunger
valve includes a venturi section which creates a vacuum within
the valve head assembly and treatment tank to draw saturated
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brine solution through the treatment tank and into the valve
head. A solenoid valve is disposed dowristream of the plunger
valve and is actuated to allow fluid flow through the plunger
valve. All fluid which flows through the plunger valve also
flows through the solenoid valve. A problem with such solenoid
valves is that they typically have a relatively low flow rate,
e.g., 5 gallons/minute maximum, which accordingly limits the
regeneration time of the water treatment tank. Moreover, since
all of the fluid flows through the solenoid valve when the
solenoid valve is in an open position, debris and foreign matter
within the fluid may lodge within the solenoid valve and cause
improper functioning thereof.
It is also known in the art to use counter current and
pulsating flow through a treatment tank to reduce the amount of
time required to regenerate the resin bed and to more fully
recharge the resin bed and to prevent channeling or fluidizing of
the resin bed. For example, U.S. Patent No. 5,108,616 (Kunz)
discloses an ion exchange water treatment system using a pulsed,
counter current flow of regenerant through the treatment tank.
7'he duration of the pulsations and the time period between
pulsations is such that the ion exchange granules making up the
resin bed within the treatment tank are not substantially mixed
ciuring the regenerating process.
An advantage of solenoid valves is that they may be quickly
opened and closed to thereby decrease the amount of time required
to regenerate a particular treatment tank.
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What is needed in the art is a water treatment system which
induces a flow of regenerant through the treatment tank and into
the valve head assembly very quickly, using less water and time
in comparison with conventional units.
A further need is a system which utilizes diaphragm valves
to quickly direct water in a particular direction within the
valve head, while eliminating problems of debris buildup within
and low flow rate through such a diaphragm valve.
An additional need is a water treatment system which allows
various time periods for certain segments of the regeneration
process to be quickly and easily altered depending upon water
conditions, water usage, high or low pressure, etc.
A still further need is a water treatment system which
allows for lost or unaccounted for water that has gone through
the system and thereby eliminates overlap conditions associated
therewith and rebuilds the bed if an overlap condition occurs.
An additional need is a water treatment system which
monitors exact water usage of one or more tanks within a water
treatment system and regenerates each particular tank according
to the exact amount of water used by that tank.
A further additional need is a water treatment system which
utilizes a vacuum pressure within the valve head to create a
relatively strong suction pressure within the treatment tank and
thereby removes substantially all the gases therein, i.e.,
degassifies the interior of the treatment tank and draws the
regenerate in an undiluted state.
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The present invention provides a valve head assembly which
uses a fast acting valve to effect a flow of fluid through the
valve head assembly, while at the same time having only a small
oortion of fluid flowing through the solenoid valve, relative to
'the total amount of fluid flowing through the valve head
assembly.
The invention comprises, in one form thereof, a water
treatment system including a treatment tank having an ion-
exchange mineral or filtration bed therein, and a valve head
assembly disposed on top of and in fluid communication with the
treatment tank. The valve head assembly includes a passage for
allowing a flow of fluid through the valve head assembly, a
vacuum pressure creating device disposed within the passage, a
cirain disposed within the passage and at a downstream side of the
,racuum pressure creating device, and a valve disposed within the
passage and at a downstream side of the vacuum pressure creating
device. The valve is movable to an open position and a closed
position for allowing fluid flow through the vacuum pressure
creating device, whereby a portion of fluid flows through the
drain and a lesser remaining portion of fluid flows through the
valve when the valve is in the open position.
An advantage of the present invention is that the valve head
assembly induces a flow of brine through. the treatment tank and
into the valve head assembly very quickly, causing faster
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exchange with 100% regenerant in comparison with conventional
units, thus saving water in the process.
A further advantage is that fast acting valves are used to
quickly direct water in a particular direction within the valve
head, while eliminating problems of debris buildup within and low
f_low rate through the valve.
An additional advantage is that various time periods
corresponding to certain segments of the regeneration process can
be quickly and easily altered depending upon water conditions,
water usage, hardness et:c.
A still further advantage is that lost water is allowed for,
thereby eliminating overcapacity conditions associated therewith.
An additional advaritage is that exact water usage of one or
more tanks is monitored and each particular tank can be
regenerated according to the exact amount of water used by that
t: ank .
A further advantage is that a vacuum pressure within the
valve head is used to create a relatively strong suction pressure
within the treatment tank and thereby remove substantially all
the gases therein, i.e., degassify the interior of the treatment
tank.
The above-ment.ioned and other features and advantages
of this invention, and the manner of attaining them, will become
more apparent and the invention will be better understood by
reference to the following description of an embodiments of the
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invention taken in conjunction with the accompanying drawings,
wherein:
Fig. 1 is a schematic illustration of an embodiment of the
present invention, showing fluid flow during an in-service mode;
Fig. 2 is a schematic illustration of the embodiment of Fig.
1, showing fluid flow during a brine draw mode;
Fig. 3 is a schematic illustration of the embodiment of Fig.
1, showing fluid flow during a pulsating rinse mode;
Fig. 4 is a schematic illustration of the embodiment of Fig.
1, showing fluid flow during a purge mode;
Fig. 5 is a schematic illustration of the embodiment of Fig.
1, showing fluid flow during a brine tank refill mode;
Fig. 6 is an enlarged view of the valve head assembly shown
in Figs. 1-5;
Fig. 7 is an electrical schematic of an embodiment of the
processor of the present invention;
Fig. 8 is a flow chart of the decisional steps carried out
by an embodiment of a processor of the present invention; and
Fig. 9 is a layered, fragmentary top view of the valve head
assembly shown in Fig. 6.
Corresponding reference characters indicate corresponding
parts throughout the several views. The exemplification set out
herein illustrates one preferred embodiment of the invention, in
one form, and such exemplification is not to be construed as
limiting the scope of the invention in any manner.
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Referring now to the drawings and more particularly to
Figs. 1-5, there is shown a water treatment system 10 of the
present invention, including treatment tank assemblies 12, 14,
nianifold 16 and processor or electronic logic control board 18.
Each treatment tank assembly 12, 14 includes a valve head
assembly 20 mounted on top and disposed in fluid communication
with an interior of a treatment tank 22. Valve head assembly 20
(Figs. 6 and 9) includes a body 24 and cap 26 separated by a disk
28. Cap 26 includes a spacer 27. A flexible membrane 30, such
as an elastomeric membrane, overlies disk 28 and is disposed
between cap 26 and disk 28. Body 24 includes a flange 32
disposed near a bottom end thereof and engages a treatment tank
22, such as shown in Figs. 1-5. Body 24 also includes a
plurality of passages for allowing a flow of fluid through valve
head assembly 20. To wit, body 24 includes a first passage 32 in
which is disposed a plunger valve 34. A compression spring 38
biases plunger valve 34 in a downward, closed position, whereby
plunger valve 34 is in contact with shoulder 40.
Body 24 also includes a second passage 42 in which is
disposed a poppet-type plunger valve 44. Disposed at a bottom
end of valve 44 are first and second annular sealing rings 46,
48, which abut shoulders 50, 52, respectively. Disposed at an
upper end of valve 44 is a flexible seal 54 which allows a flow
of fluid therepast in an upward direction, but prevents a flow of
fluid therepast in a downward direction.
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Valve 44 includes a longitudinally extending opening 56 in
which is disposed an insert 58 defining a venturi section 70.
Each of valve 44 and insert 58 have radially extending openings
62 which allow a flow of fluid into verzturi section 60. Plunger
valve 44 also includes a plurality of radial openings 94 and a
longitudinal opening 96 allowing a flow of fluid therethrough and
into venturi section 60. Disposed between valve 44 and second
passage 42 is a chamber 64.
Disposed above second passage 42 is a third passage 66, in
which is inserted a cylindrical sleeve 68. A plurality of 0-ring
seals 70 provide a seal between third passage 66 and sleeve 68.
Body 24 also includes an inlet passage 72, outlet passage 74
and drain passage 76, each of which are respectively, fluidly
connected to chamber 64, chamber 78 and chamber 80 via radial
passages 82, 84 and 86.
Additional openings within body 24 include longitudinally
extending openings 88, 90 providing communication between chamber
64 and the interior of treatment tank 22; and a passage 92
providing communication between chamber 80 and a valve described
hereinafter. A fourth passage 69 defines a chamber 71 which is
disposed below plunger valve 34. A radiaily extending opening
120 is in communication with the exterior of body 24 and chamber
71. A radially extending opening 122 is in communication with
the exterior of body 24 and chamber 78.
Disposed between plunger valve 44 and disk 28 is a
compression spring 93 which biases plunger valve 44 toward a
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first, closed position. Flexible membrane 30, disposed on top of
disk 28, includes a disk 98 with a central opening 100 therein.
Disposed within opening 100 is a screened filter 99. Flexible
membrane 30, disk 98 and cap 26 define a chamber 102
therebetween. Chamber 102 is also disposed in fluid
communication with a passage 104 formed in cap 26.
Figs. 1-5 illustrate treatment tank assemblies 12, 14
interconnected by manifold 16 and electronic logic control board
18, whereby one or both of treatment tank assemblies 12, 14 may
be placed in an in-service mode or one regeneration mode. Logic
control board 18 is shown connected to a user interface device or
riumeric keypad 106 allowing a user to manually control logic
control board 18, and in turn control treatment tank assemblies
12, 14. Logic control board 18 is also connected to a first
solenoid valve 108 via line 110, a second solenoid valve 112 via
line 114 and a third solenoid valve 116 via line 118. Each of
treatment tank assemblies 12, 14 are constructed substantially
the same in the embodiment shown, and thus have like reference
numbers. For purposes of clarity, however, not all of the
reference numbers have been indicated on treatment tank assembly
1.2.
First valve 108 has an inlet line 124 disposed in
communication with passage 92 of body 24 (Fig. 6). First valve
1.08 also includes an outlet line 126 disposed in communication
with each of passage 104 and chamber 102 within cap 26, and
regenerant induction line 128 via outlet line 130. Disposed
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within induction line 128 is a ball valve 132 allowing a flow of
fluid in a downward direction, and disposed within outlet line
1.30 is a spring loaded check valve 134 allowing a flow of
pressurized fluid in an upward direction.
Second valve 112 includes an inlet line 136 which is
connected to radially extending opening 122 and chamber 71 (Fig.
6) and an outlet line 138 connected to an inlet line 140 of third
valve 116. A ball valve 141 disposed between inlet line 140 and
induction line 128 allows a flow of fluid in an upward direction.
A brine tank 142 is connected to regenerant induction line
128 and has a regenerant 144 disposed therein, such as sodium
chloride. A float valve assembly 146 controls a level of liquid
within brine tank 142, as is known.
Manifold 16 generally includes three T-pipes coupled
together for convenience purposes. A first pipe 148 includes
outlets 150 which are connected to respective inlet passages 72
(Fig. 6), and an inlet 152 which receives pressurized liquid from
an external source (not shown), such as a water pump. Second
pipe 154 includes inlets 156 which are connected to respective
flow meters 158, which in turn are connected to outlet passage 74
(Fig. 6). Second pipe 154 also includes an outlet 160 connected
to a line for supplying treated water to a faucet or the like.
Third pipe 162 includes inlets 164 connected to drain passage 76
(Fig. 6) and an outlet 166 connected to a drain pipe.
Flow meters 158 (shown in greater detail in Fig. 6) include
first housing part 168 sealingly coupled to a second housing part
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6.)
L70. A wheel 172 having a plurality of v anes is carried by a
shaft 174 which in turn is rotatably supported by first and
second housing part 168, 170. The interconnection between shaft
174 and first and second housing parts 168, 170 may include
bearings. Moreover, the configuration of the vanes within wheel
172 is such that wheel 172 rotates upon a flow in either
ciirection within flow meter 158. Wheel 172 includes at least one
magnet 176 disposed therein which rotates past a sensor 178 upon
rotation of wheel 172. Sensor 178 is connected via line 180
(Fig. 1) to logic control board 18.
Referring now to Figs. 1-5, operation of the present
invention will be described. For each of the modes of operation
described above, logic control board 18 controls the length of
time in which first valve 108, second valve 112 and third valve
116 are in an open or closed position.
Fig. 1 discloses a mode of operation wherein each of
treatment tank assemblies 12, 14 are in ar1 in-service mode.
Poppet-type plunger valve 44 is in the downward, closed position;
and plunger valve 34 is in the upward, open position. Water
f'lows through first pipe 148 and into chamber 64 of valve head
assembly 20. The water then flows downward through longitudinal
openings 88, 90, through filter 181, and into treatment tank 22.
The water flows in a downward direction through resin bed 182,
whereby impurities such as calcium and magnesium are removed from
the water via ion exchange. The water then flows through a
filter 184 and into vertical pipe 186. The pressurized water
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moves plunger valve 34 to the upright, open position and flows
t-_herepast to outlet 160 of second pipe 154.
Fig. 2 illustrates treatment tank assembly 12 in an in-
service mode and treatment tank assembly 14 in a brine draw mode
of operation. Fluid flow through treatment tank assembly 12 is
as described above with regard to Fig. 1. With regard to
treatment tank assembly 14, first valve 108 is in an open
position and second and third valves 112 and 116 are in a closed
position. When third valve 116 is closed, pressurized fluid is
rio longer supplied within cap 26. When first valve 108 is
opened, water flows past seal, 54 of plunger valve 44 and causes
plunger valve 44 to move to the upward, open position, as shown.
The pressurized water within chamber 80 causes flexible membrane
30 to move to the upper position shown, whereby water may flow
through inlet line 124 to first valve 108. The water then flows
through outlet line 126 and into chamber 102. The small diameter
central opening 100 (Fig. 6) allows a correspondingly small
amount of fluid to flow therethrough. The amount of water thus
flowing through first valve 108 is regulated by varying the
diameter of central screened opening 100. In contrast, passage
92 has a relatively large diameter. Therefore, substantially all
the water flowing into chamber 80 flows out through passage 92,
and a lesser amount of the fluid flowing through chamber 80 flows
through first valve 108.
When plunger valve 44 is in the upward position whereby
annular sealing ring 46 engages shoulder 50, water flows through
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radial openings 94 and longitudinal opening 96 into venturi
section 60. Venturi section 60 creates a low pressure within,
chamber 64, which in turn induces a flow of water through
longitudinal openings 88, 90 and first pipe 148. The flow of
water into chamber 64 in turn induces a flow of brine from brine
tank 142 through induction line 128, radially extending opening
120, filter 181, vertica.l pipe 186 and fiiter 184. As in
apparent from Fig. 2, a counter-current regeneration is effected,
wherein the flow of water through treatment assembly 14 during an
in-service mode is opposite to the flow of water through
treatment tank assembly 14 during a brine draw mode.
Fig. 3 illustrates a mode of operation wherein treatment
tank assembly 12 is in an in-service mode and treatment tank
assembly 14 is in a pulsating rinse mode. It will be noted that
plunger valve 44 is an upper position for inducing a.flow of
liquid as described above with regard to Fig. 2. However, rather
than receiving a supply of water from brine tank 142 via
induction line 128, second valve 112 is moved to an open position
whereby pressurized and treated water from treatment tank
assembly 12 flows through inlet line 136 and into treatment tank
22 in a counter current direction. The pressurized water within
inlet line 140 also moves ball valve 141 to a closed position as
shown, wherein fluid does not flow into brine tank 142.
During the pulsating rinse mode, logic control board 18
controls first valve 108 whereby at least two regeneration
options may be effected. To wit, keypad 108 may be utilized to
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select either a full pulse regeneration, a half pulse
regeneration, no pulse regeneration and filter regeneration.
During full pulse regeneration, 100% of the pulse rinse is
activated, which means valve 108 is on all the time. Valve 112
is on one second and of.f three seconds, during full pulse
regeneration. During no pulse regeneration, only a maximum of
12% of the pulse program is activated (to prevent channeling of
the resin bed), which means valve 108 and 112 are on the majority
of the time. During ha:Lf pulse regeneration, 50% of the full
pulse program is activated, using the same valve as stated above.
With the balance of the cycle valve 112 stays on. During filter
regeneration, brine cycle and refill cycle is significantly
reduced to create a vacuum in the tank at about 10% of the cycle
time based on capacity. The refill cycle is reduced accordingly.
An extended full pulse regeneration is initiated during the
filter regeneration. These regeneration options are on time or
ciemand mode.
It will be appreciated from Fig. 3 that treated water is
utilized from treatment tank assembly 12 to rinse the resin bed
within treatment tank assembly 14. The embodiment as shown not
only monitors treated water which flows out through outlet 160,
but also monitors the flow of water used to rinse the resin bed
in a parallel treatment tank assemblyd That is, at least one
flow meter 158 provides input pulses to logic control board 18,
which in turn reduces the preset amount stored in memory
corresponding to the volume of water transported from the
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treatment tank assembly during an in-service mode prior to
regeneration thereof. Logic control board 18 receives input
pulses from at least one flow meter 158 representing a volume of
water flowing therepast. Each of treatment tank assemblies 12,
1.4 has a capacity at which the treatment tank assembly must be
r-egenerated. For example, each treatment tank assembly shown in
F'igs. 1-5 has a capacity of exchanging 5,000 grains of hardness.
F'or a particular application, the untreated water received via
first pipe 148 has a hardness which falls within a known range
per gallori, e.g., 6-10 parts per million. It is thus possible to
calculate how many gallons of water may be transported through
second pipe 154 prior to regeneration of the corresponding
treatment tank assembly. Rather than using two flow meters 158
as shown in Figs. 1-5, it may also be possible to use a single
flow meter attached to outlet 160 of second pipe 154.
Fig. 4 illustrates another mode of operation wherein
treatment tank assembly 12 is in an in-service mode and treatment
tank assembly 14 is in a purge or fast rinse mode. The flow
paths within treatment tank assembly 14 are the same as described
above with regard to the pulsating rinse mode shown in Fig. 3.
However, rather than opening and closing first valve 108 to
provide a pulsating rinse, first valve 108 is instead maintained
in an open position whereby treated water from treatment tank
assembly 12 continuously flows through treatment tank 22 in a
counter current direction.
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Fig. 5 illustrates another mode of operation of the present
invention wherein treatment tank assembly 12 is in an in-service
mode, and treatment tank assembly 14 is in a brine tank refill
mode. As is apparent, treated water is available to second pipe
154 from treatment tank assembly 14. In addition, first valve
108 and second valve 112 are in a closed position and third valve
116 is in an open position allowing treated water to flow both in
an upward direction through outlet line 130 and a downward
direction into brine tank 142 through induction line 128. The
treated water flowing through outlet line 130 then flows through
check valve 134, outlet line 126 and into chamber 102 for moving
flexible membrane against disk 28 and closing passage 92 and
drain passage 76. The treated water flowing in a downward
direction through induction line 128 fills brine tank 142 to a
predetermined level, as controlled by float valve assembly 146.
Fig. 7. is a schematic illustration of the circuitry of
logic control board 18 shown in Figs. 1-5. Various components
include microcontroller 188, key pad 106, key pad lock 190,
amplifier/driver 192, display device 194 (such as an LED
display), AND gates 196, 198, control gates 200, 202, 204, 206,
208 and 210, treatment tank solenoid valve control ports 212,
214, manual refill switch 216, latched line decoders 197, 199,
and flow meter sensor ports 201. Microcontroller 188 receives
input data from flow meter sensor ports 201, and provides output
signals used for controlling solenoid valve control ports 212,
214. Control gates 200, 202, 204, 206, 208 and 210 are
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1.
interposed between microcontroller 188 and solenoid valve control
ports 212, 214, and respectively control the opening and closing
of solenoid valves 108, 112 and 116. Display device 194 can be
used to selectively display a total flow amount through a
particular tank since a last regeneration, a total flow amount
through the system since a predetermined point in time, an
:indication of which tank(s) are in an in-service mode or
regeneration mode, an overlap amount for a particular tank, a
preset amount for a partLicular tank, and other indicia of system
performance and operation.
In the embodiment of the circuitry shown in Fig. 7,
alternating current power is used to drive solenoid valves 108,
112 and 116. Conventional designs use direct current power to
cirive solenoid valves, which results in overheating and failure
of the solenoid valves. The present invention therefore
overcomes a problem of conventional designs by utilizing
alternating current power.
Fig. 8 illustrates a flow chart of the logic carried out by
control board 18. Block 216 represents a selective mode
evaluation parameter corresponding to either a time mode of
operation or a demand mode of operation. For a time mode of
operation, a particular treatment tank assembly is regenerated
after a particular period of time. For a demand mode of
operation, a particular treatment tank assembly is regenerated
after a particular volumetric amount of liquid has been
transported from a treatment tank assembly. If a time mode of
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operation is selected (line 220), a regeneration evaluation block
222 is utilized. In coaritrast, if a demand mode of operation is
elected, a regeneration evaluation block 224 is used. Other data
inputs to regeneration evaluation block 222 include time data
parameter from block 218 representing a particular amount of time
at which a treatment tank assembl.y is regenerated; and a time
value of a system clock from block 226. Data inputs to
regeneration evaluation block 224 include sensed pulses from a
turbine or flow meter (block 228) via line 230; demand data
parameter from block 232 representing a particular volume at
which the treatment tank assembly is to be regenerated; and a
time value from a system clock in block 226.
When regeneration evaluation block 224 determines that a
preset amount of water has been transported from a particular
treatment tank assembly, the particular treatment tank assembly
to be regenerated is rentoved from memory as a tank available for
an in-service mode (block 232) and regeneration of the particular
treatment tank assembly occurs in block 234. After regeneration
of the particular treatment tank assembly is completed, the
treatment tank assembly is placed back in memory as being
available for an in-service mode of operation in block 236. The
"system tank parameters" (block 235) corresponds to physical data
associated with a particular tank used, e.g., such as tank
capacity and grains. Such data can be in the form of electronic
data stored in a memory. Regeneration data tables (block 237)
correspond to data indicating when a particular tank should be
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regenerated or timed modes within the regeneration, e.g.,
hardness of water, rinse modes, half pulse mode, etc.
While this invention has been described as having a
preferred design, the present invention can be further modified
within the spirit and scope of this disclosure. This application
is therefore intended to cover any variations, uses, or
adaptations of the invention using its general principles.
Further, this application is intended to cover such departures
from the present disclosure as come within known or customary
practice in the art to which this invention pertains and which
fall within the limits of the appended claims.
