U.S. patent application number 13/625945 was filed with the patent office on 2014-03-27 for method and apparatus for energy efficient wash appliances.
The applicant listed for this patent is MARK R. MCDONALD. Invention is credited to MARK R. MCDONALD.
Application Number | 20140083460 13/625945 |
Document ID | / |
Family ID | 50337652 |
Filed Date | 2014-03-27 |
United States Patent
Application |
20140083460 |
Kind Code |
A1 |
MCDONALD; MARK R. |
March 27, 2014 |
METHOD AND APPARATUS FOR ENERGY EFFICIENT WASH APPLIANCES
Abstract
An electronic controller used with a washing appliance, such as
a dishwasher, operatively connected to a hot water delivery system
having a hot water heater, hot water delivery piping, and a
circulation pump that when activated circulates water in the
delivery piping back to the hot water heater. The washing appliance
structured to perform a cleaning process that includes a pre-wash
cycle and a wash cycle that utilizes hot water received from the
hot water delivery piping. The pre-wash cycle having a water fill
step, a water spray step, and a water drain step. The electronic
controller on sensing the completion of the water fill step, or,
alternatively, the water spray step, sends a first signal to the
circulation pump causing the pump to become activated, and upon
sensing the completion of the water spray step, or, alternatively,
the water drain step, sends a second signal to the circulation pump
causing the deactivation of the pump.
Inventors: |
MCDONALD; MARK R.;
(Hattisburg, MS) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MCDONALD; MARK R. |
Hattisburg |
MS |
US |
|
|
Family ID: |
50337652 |
Appl. No.: |
13/625945 |
Filed: |
September 25, 2012 |
Current U.S.
Class: |
134/18 ;
134/57D |
Current CPC
Class: |
A47L 15/0047 20130101;
A47L 2501/01 20130101; A47L 15/0021 20130101; A47L 2501/36
20130101 |
Class at
Publication: |
134/18 ;
134/57.D |
International
Class: |
A47L 15/42 20060101
A47L015/42 |
Claims
1. An electronic controller for use with a hot water delivery
system comprising a hot water heater, hot water delivery piping and
a circulation pump operatively connected to circulate hot water
from the hot water heater through the hot water delivery piping and
back to the hot water heater when the circulation pump is
activated, and for use with a washing appliance having a hot water
inlet valve operatively connected to the hot water delivery system
to receive hot water from the hot water delivery piping when the
hot water inlet valve is open, wherein the washing appliance
performs a washing process comprising a pre-wash cycle and a wash
cycle, the pre-wash cycle including a water fill step, a water
spray step, and a water drain step, the improvement to which
comprises: a. the electronic controller upon sensing completion of
the water fill step or the water spray step or initiation of the
water drain step being constructed to send a first signal to
activate the circulation pump, and b. the electronic controller
upon sensing the completion of the water spray step or the water
drain step to send a second signal to deactivate the circulation
pump.
2. The electronic controller according to claim 1 wherein the
electronic controller upon sensing initiation of the water drain
step being constructed to send a first signal to activate the
circulation pump, and upon sensing the completion of the water
drain step to send a second signal to deactivate the circulation
pump.
3. In an assembly for operation of a dishwasher including: a. the
dishwasher having a body forming an interior cavity having a sump
area, a water inlet valve operatively attachable to a hot water
source, a washing system, a heater system, a drain system, and an
electronic controller operatively attached to (i) the water inlet
valve to close or open the water inlet valve, (ii) upon receiving
wash process signals from the controller, the washing system to
initiate at least one of a pre-wash cycle, a wash cycle and a rinse
cycle, (iii) upon receiving water draining signals from the
controller, the drain system to initiate a water drain step to
remove water from the dishwater sump, and (iv) upon receiving
drying cycle signals from the controller the heater system to
initiate a drying cycle; b. a hot water delivery system including a
hot water heater, a first pipe operatively connected to the hot
water heater to receive heated water from the hot water heater and
operatively connected to a circulation pump constructed when
activated to pump heated water from the first pipe to a second pipe
operatively connected to the hot water heater for delivery of the
heated water back to the hot water heater for reheating; the
improvement to which comprises the electronic controller
constructed to transmit a first signal representative of (i)
completion of the water fill step, (ii) initiation of the water
spray step, (iii) completion of the water spray step or (iv)
initiation of the water drain step of the pre-wash cycle to the
circulation pump to activate the circulation pump, and to transmit
a second signal representative of the completion of the pre-wash
cycle to the circulation pump to deactivate the circulation
pump.
4. The assembly of claim 3 further comprising the electronic
controller constructed to transmit a third signal to the water
inlet valve to open the water inlet valve and permit the heated
water to flow though the water inlet valve and into the dishwasher
cavity.
5. A method utilizing heated water from a hot water heater for
supplying hot water at a pre-determined temperature to a dishwasher
upon initiation of a wash cycle of the dishwasher by an electronic
controller transmitting a signal to open a water inlet valve
operatively attached to the hot water heater by a hot water deliver
piping to receive the hot water upon opening of the water inlet
valve, wherein the hot water delivery piping comprises a first pipe
operatively attached at one end to the hot water heater and
operatively attached at an opposite end to the water inlet valve, a
second pipe operatively attached at one end to the first pipe and
operatively attached to an intake port of a circulation pump, and a
third pipe operatively attached at one end to a discharge port of
the circulation pump and operatively attached at an opposite end to
the hot water heater; comprising the steps of: a. sending a first
signal from the controller upon activation of a pre-determined
pre-wash cycle to the circulation pump to activate the circulation
pump, and b. sending a second signal from the controller upon
completion of a water drain step of the pre-determined pre-wash
cylce to the circulation pump to de-activate the pump.
6. A method utilizing heated water from a hot water delivery system
comprising a hot water heater, a hot water delivery piping
operatively attached to the hot water heater to receive hot water
from the hot water heater and to circulate the heated water back to
the hot water heater upon activation by a controller of a
circulation pump operatively attached to the hot water delivery
piping, the hot water delivery piping operatively connected to a
dishwasher to deliver hot water through the hot water delivery
piping at a pre-determined temperature to the dishwasher upon
initiation of a wash cycle of a pre-determined washing process of
the dishwasher, comprising: a. sending to the circulation pump a
first signal from the controller upon the controller sensing
completion of a water fill step or a water spray step or initiation
of a water drain step of a pre-determined pre-wash cycle of the
washing process, the first signal causing activation of the
circulation pump, and b. sending to the circulation pump a second
signal from the controller after a predetermined period of time
prior to the initiation of the wash cycle of the washing process,
the second signal causing deactivation of the circulation pump.
7. The method according to claim 6 wherein a. the dishwasher
comprises a dishwasher controller that transmits control signals to
selected components of the dishwasher to initiate and complete the
water fill step, the water spray step, and the water drain step of
the pre-wash cycle; b. the controller is the dishwasher controller;
c. the water fill step includes the controller sending a first
water inlet valve signal to the water inlet valve causing opening
of the water inlet valve operatively connected to the hot water
delivery piping to receive hot water from the hot water heater,
maintaining the water inlet valve opened for a pre-determined
period of time to permit the received hot water to collect in an
interior sump area of the dishwasher, and upon expiration of the
pre-determined time the controller sending a second water inlet
valve signal to the water inlet valve causing closing of the water
inlet valve; d. the water spray step includes the controller
sending a first sump pump signal to the sump pump of the dishwasher
causing activation of the sump pump operatively positioned upon
activation to collect the hot water collected in the interior sump
area and to deliver the collected hot water to a spray arm having
nozzles positioned to direct the collected hot water to contact
articles to be washed, and the controller sending a second sump
pump signal to the sump pump causing deactivation of the sump pump
to terminate the collection of the hot water from the interior sump
area; e. the water drain step includes the controller sending a
first drain valve signal to a drain valve of the dishwasher located
in the interior sump area causing opening of the drain valve to
permit water collected in the interior sump area to be removed from
the dishwasher, the controller sending a first drain pump signal to
a drain pump of the dishwasher positioned to collect water in the
interior sump area causing activation of the drain pump to direct
the collected water to the drain valve, after a pre-determined
period of draining time, the controller sending a second drain pump
signal to the drain pump causing deactivation of the drain pump and
sending a second drain valve signal to the drain valve causing
closing of the drain valve; f. sending the first signal by the
controller to the circulation pump upon sending one of the
following signals (i) second water inlet valve signal, (ii) first
sump pump signal, (iii) second sump pump signal, (iv) first drain
valve signal, or (v) first drain pump signal.
8. The method according to claim 7 wherein a. the first signal is
sent to the circulation pump when the second water inlet valve
signal is sent to the water inlet valve, and b. the second signal
is sent to the circulation pump upon sending one of the following
signals: (i) second sump pump signal, (ii) the first drain valve
signal, (iii) the first drain pump signal, (iv) the second drain
valve signal, or (v) the second drain pump signal.
9. The method according to claim 7, wherein: a. the first signal is
sent to the circulation pump when the first sump pump signal is
sent to the sump pump, and b. the second signal is sent to the
circulation pump upon sending one of the following signals: (i)
second sump pump signal, (ii) the first drain valve signal, (iii)
the first drain pump signal, (iv) the second drain valve signal, or
(v) the second drain pump signal.
10. The method according to claim 7, wherein: a. the first signal
is sent to the circulation pump when the second sump pump signal is
sent to the sump pump, and b. the second signal is sent to the
circulation pump upon sending one of the following signals: (i) the
second drain valve signal, or (ii) the second drain pump
signal.
11. The method according to claim 7, wherein: a. the first signal
is sent to the circulation pump when the first drain valve signal
or the first drain pump signal is sent to the sump pump, and b. the
second signal is sent to the circulation pump upon sending one of
the following signals: (i) the second drain valve signal, or (ii)
the second drain pump signal.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates in general to washing appliances, and
more particular to apparatus and methods for energy efficiently
operating a dishwasher.
[0003] 2. Prior Art
[0004] It is known that one of key factors for a dishwasher to
properly clean dishes, cookware, silverware, glassware and other
similar articles is supplying the dishwasher during the washing
cycle with hot water at a predetermined temperature, typically at
least 120.degree. F. In a typical residential setting this hot
water is supplied by a conventional hot water heater that is used
to supply hot water not only to the dishwasher, but other water
outlets such as found in showers, bath tubs, wash basins and
kitchen sinks, as well as other washing appliances, such as a
clothes washing machine. In this setting generally cool water from
a municipal water company, or similar source, is supplied to the
hot water heater under low pressure (typically, 15-120 psig). The
hot water heater has gas or electrical heating units that then heat
the water to the desired temperature. Because the hot water will be
used in a shower, bath tub or wash basin, the temperature can not
be set above about 120.degree. F. to prevent burns to a person's
body or hands. This hot water is then discharged from the hot water
heater and through plastic or metal pipes to various hot water
outlets, including the dishwasher.
[0005] The problem is that the discharged hot water cools as it
sits in the pipes waiting for the dishwater water inlet valve or
the hot water faucet of the other devices to be opened. As a result
the water in the pipes is likely to be at some temperature
significantly less than the desired 120.degree. F., resulting in
energy inefficient washing of the dishes or other articles. It is
not until the cooled water has been emptied from the pipes and
replaced with fresh hot water from the hot water heater at the
desired 120.degree. F. does one obtain at the dishwasher or hot
water sink faucets or other washing appliances hot water at the
desired temperature. Considering that the distance between the hot
water heater and the dishwasher can be significant, not only is
there a large water waste and loss of the energy used to initially
heat the now cooled water, but it will likely take considerable
time before hot water at the desired temperature arrives at the
dishwasher water intake valve. In the case of a dishwasher this
means that the dishes and other articles are not being cleaned for
a significant portion of the dishwasher cleaning process at the
temperature necessary to achieve the desired level of cleaning.
This requires the dishwasher cleaning process to include more or
longer washing cycles than would otherwise have been required.
[0006] One solution has been to utilize a return line that permits
the hot water to be continuously circulated out of and back into
the hot water heater when no hot water valve has been opened to
better insure that the circulating water remains at the desired
120.degree. F. temperature. Although this solution does result in
maintaining the water at the desired temperature for effective
cleaning, the energy costs to maintain the water at the desired
temperature during the circulation, as well as the capital cost to
install the return line makes such solution impractical. The
capital cost in such circulation systems can be reduced by
re-circulating the cooled hot water back to the hot water heater
using the existing cold water line used to deliver cold water to
the various appliances or sink faucets. However, the energy cost to
continuously pump and reheat the water in the circulation lines
makes even these modified systems economically impractical. Also,
it is not possible for the other connected cold water outlets to
receive cold water during the circulation process. Alternatively,
it is necessary to install various control devices to stop the
re-circulation when the home owner wants to use the cold water. In
an attempt to reduce the energy costs of such systems more modern
systems install a pump and pump controller in the circulation lines
to reduce the time that the water is being circulated. In these
systems until the pump is activated there is no circulation of the
water through the circulation lines. To activate the pump a timer
is utilized to regulate the time periods during a day that the pump
will run. It is also known to utilize a temperature gauge to
measure the water temperature in the circulation lines and to
activate the pump once the water temperature has dropped below the
set level. Finally, some the pump controllers will permit a manual
activation of the pump. These systems still do not overcome the
problems associated with using the cold water lines to re-circulate
the cooled hot water back to the hot water heater for reheating to
the desired 120.degree. F. Although the use of such activation
controls and equipment are in many cases effective in reducing the
energy costs, the amount of reduction is generally less than what
is desired. Part of the problem of such systems is that there is
not some normal short time period in which one would wish to
operate the dishwasher or other washing appliance. Thus, the pump
may not be running at the desired time or may be running for too
long a period to achieve the desired saving. In addition, manual
activation of the pump controller may be very inconvenient
depending on where the pump and pump controller are installed in
the residence, or one may forget to activate the pump controller
and thus lose all energy saving benefits.
[0007] A method or apparatus that would automatically provide real
on-demand hot water at the desired 120.degree. F. to a dishwasher
or other washing appliance during its washing process at low energy
costs would be of particular use to the home appliance
industry.
OBJECTS AND SUMMARY OF THE INVENTION
[0008] Therefore, one object of this invention is to provide an
electronic controller that will automatically activate a pump
operatively positioned in a hot water delivery piping within a
predetermined time period before a washing appliance, such as a
dishwasher is activated to begin the wash cycle of the washing
process.
[0009] Another objective of this invention is to provide on-demand
hot water at a desired temperature to a washing appliance that
permits other hot water faucets to receive the hot water at the
same time as the washing appliance.
[0010] Still another object of this invention is to provide an
electronic controller that will activate a circulation pump in a
hot water delivery line upon receipt of a signal from the washing
appliance controller representative of a predetermined time period
before a washing appliance is activated to begin its wash
cycle.
[0011] A further object of this invention is to provide a
relatively inexpensive and easy to install electronic connection
between the dishwasher controller and the pump controller
permitting a signal from the dishwasher controller to be received
by the pump controller for the purpose of activating the
circulation pump a predetermined period of time prior to beginning
the dishwasher wash cycle.
[0012] A still further object of this invention is to provide a
relatively inexpensive and easy to install after-market electronic
connection between the dishwasher controller and the pump
controller permitting a signal from the dishwasher controller to be
received by the pump controller for the purpose of activating the
circulation pump a predetermined period of time prior to beginning
the dishwasher wash cycle.
[0013] An alternative object of this invention is to provide an
energy efficient method to wash dishes, pots and pans, silverware,
glassware and other similar objects utilizing during a dishwasher
washing cycle hot water at a desired temperature.
[0014] Another alternative object of this invention is to provide a
method utilizing a signal from the dishwasher controller to ensure
an energy efficient delivery from a hot water heater of hot water
at a desired temperature to the dishwasher during the washing
cycle.
[0015] A still further object of this invention is to provide a
method utilizing a signal from the dishwasher controller
representative of the completion of the water fill step, or,
alternatively, the water spray step, of the washing process to
activate the circulation pump, and utilizing a signal from the
dishwasher controller representative of the completion of the water
spray step, or, alternatively, the completion of the water drain
step of the washing process to deactivate the circulation pump.
[0016] These and other objects of this invention shall become
apparent from the ensuing drawings and descriptions of the
invention.
[0017] Accordingly, an electronic controller for use with a hot
water delivery system comprising a hot water heater, hot water
delivery piping and a circulation pump operatively connected to
circulate hot water from the hot water heater through the hot water
delivery piping and back to the hot water heater when the
circulation pump is activated, and for use with a washing appliance
having a hot water inlet valve and operatively connected to the hot
water delivery system to receive hot water from the hot water
delivery piping when the hot water inlet valve is open, wherein the
washing appliance performs a washing process comprising a pre-wash
cycle and a wash cycle, the pre-wash cycle including a water fill
step, a water spray step, and a water drain step, the electronic
controller constructed (a) upon sensing completion of the water
fill step or the water spray step to send a first signal to
activate the circulation pump and (b) upon sensing the completion
of the water spray step or the water drain step to send a second
signal to deactivate the circulation pump.
[0018] The foregoing has outlined rather broadly the features and
technical advantages of the present invention in order that the
detailed description of the invention that follows may be
understood. Additional features and advantages of the invention
will be described hereinafter which form the subject of the claims
of the invention. It should be appreciated by those skilled in the
art that the conception and specific embodiments disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the appended claims. The
novel features which are believed to be characteristic of the
invention, both as to its organization and method of operation,
together with further objects and advantages will be better
understood from the following description when considered in
connection with the accompanying figures. It is to be expressly
understood, however, that each of the figures is provided for the
purpose of illustration and description only and is not intended as
a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings illustrate a preferred embodiment
of this invention. However, it is to be understood that this
embodiment is not intended to be exhaustive, nor limiting of the
invention. It is but one example of the construction of this
invention.
[0020] FIG. 1 is an illustration of a prior art home hot water
circulation system having dedicated hot water pipes to permit hot
water to be circulated from the hot water heater to the various
home fixtures utilizing hot water and then back to the hot water
heater.
[0021] FIG. 2 is an example of a prior art dishwasher illustrating
only those components needed for an understanding of this
invention.
[0022] FIG. 3 illustrates a typical control panel of the dishwasher
controller that permits the dishwasher operator to select the wash
procedure program to be executed by the dishwasher.
[0023] FIG. 4 is an example of a typical prior art dishwasher wash
cycle progression.
[0024] FIG. 5 is an electrical circuitry schematic of a typical
dishwasher.
[0025] FIG. 6 is an electrical circuitry schematic of the device of
this invention that can be used with the electrical circuitry
schematic of FIG. 5.
PREFERRED EMBODIMENTS OF THE INVENTION
[0026] Without any intent to limit the scope of this invention,
reference is made to the figures in describing the preferred
embodiments of the invention for use in washing dishes and other
articles in a dishwasher.
[0027] Referring now to FIG. 1, a conventional residential hot and
cold water delivery system 1 for use in a residence, office
building or similar type construction is illustrated that
incorporates a hot water return system 2 including a hot water
return line 3, a hot water circulation pump 4 that is activated and
deactivated by a timer assembly 5. In this configuration cold water
from an outside source, such as a municipal water company or water
well, is delivered under pressure of typically 15-120 psi to the
building 6 through a cold water pipe 7. For each plumbing fixture
or appliance that utilizes cold water, pipe 7 will have pipe
t-connectors to permit the cold water in pipe 7 to be circulated
through auxiliary cold water pipes 7A-7G to the respective plumbing
fixture, such as showers, toilets and wash basins, and respective
washing appliances, such as clothes washers and dishwashers. Each
of the auxiliary cold water lines 7A-7G is operatively connected
downstream to the cold water valve 8A-8G, respectively, used to
control the flow of cold water into the fixture or appliance. When
the cold water valves 8A-8G are opened cold water will flow into
the corresponding fixtures and appliances as desired. These
fixtures and appliances are typically provided with drains that
connect to the building sewer lines to permit the cold water to
flow to the sewer lines.
[0028] A portion of the cold water from the municipal water company
or water well is delivered through separate water pipe 9 to a hot
water heater 10 by its inlet valve 11. When the inlet valve 11 is
opened the cold water will flow into the hot water heater 10 that
is provided with one of the conventional heating assemblies 12 to
raise the water temperature to a predetermined level. This level is
determined by the use that will be made of the water. One use that
is common in most buildings 6 is delivery of the hot water to a
sink 13 used for a person to wash their hands. To prevent the
person from being burned by the hot water delivered to the sink 13,
the desired temperature of the water in the hot water heater 10 is
generally set at 120.degree. F.
[0029] One of the undesired features of the typical hot water
delivery system 14 is the heated water may leave the hot water
heater 10 at 120.degree. F., but if it there are no open hot water
valves open, it will sit in the hot water pipes 15 and auxiliary
hot water pipes 15A, 15C-15D, and 15F-15H and begin to cool. The
longer it sits the cooler it is likely to become. Thus, when one of
the hot water valves 16A, 16C-16D, 16F-16G or 33 is ultimately
opened the initial water flowing through the valve will not be at
the desired temperature. It is not until enough of the cooled water
flows through the opened hot water valve that hot water at the
desired temperature will be delivered through the opened hot water
valve. Depending on the distance between the hot water heater 10
and the opened hot water faucet valve, the insulation on the hot
water pipe 15 and auxiliary hot water pipes 15A, 15C-15D, and
15F-15H, the temperature within the areas of the building 6 that
the pipes 15, 15A, 15C-15D, and 15F-15H are located, and the
frequency in which the various hot water valves are opened and
closed, the longer the time and the more of the cooled water that
must be drained before hot water at the desired temperature is
received.
[0030] Not even considering the frustration for waiting until the
hot water arrives, in a typical residence occupied by a family of
four it has been estimated that up to 14,000 gallons of water per
year are wasted waiting for the hot water to arrive at the desired
temperature. In addition the cost to heat the original 14,000
gallons of water is substantially lost.
[0031] This problem is particularly acute for dishwashers 17 and
clothes washers 18, which are generally the appliances utilizing
the most hot water, whose various washing cycles depend on the hot
water entering the appliance to be at 120.degree. F. for their
washing cycles to be effective and energy efficient.
[0032] One solution to this problem has included operatively
connecting hot water pipe 15 to cold water line 7 in a manner to
permit the hot water to be circulated to hot water heater 10. This
solution has several major drawbacks. Additional plumping and
controls must be utilized to allow simultaneous demand for both
cold water and hot water at one or more of the wash basins,
showers, etc. In addition, because the cold water in cold water
line 7 is delivered under 15-120 psi pressure, this solution
requires more pump energy to overcome this cold water pressure to
effect the circulation of the hot water back to the water heater
10.
[0033] An alternate solution which is illustrated in FIG. 1 has
been the extension of the main hot water pipe 15 to circulate back
to the hot water heater 10. Although this solution requires extra
capital expense to install the extension of hot water pipe 15, this
expense can be justified by the energy savings costs. However,
these savings are significantly reduced by the energy costs to
operate circulation pump 4.
[0034] In this solution operatively connected in hot water delivery
line 15 is circulation pump 4. Pump 4 is preferably positioned in
hot water return line 3 after the last fixture or appliance that
utilizes the hot water, and, more preferably, in close proximity to
this last fixture or appliance. Thus, when activated pump 4 will
circulate the cooled hot water back to the hot water heater 10. In
current hot water delivery systems providing for circulation of the
hot water back to hot water heater 10, pump 4 is activated and
deactivated by a timer control assembly 5 that can be manually
activated or set to activate pump 4 at specific time intervals for
specified time intervals. These modified "on-demand" hot water
circulation systems permit circulation of the hot water in line 15
during predetermined times back to the hot water heater 10 to
better ensure that the hot water will be delivered at the desired
120.degree. F. to a hot water fixture valve 16A, 16C-16D, 16F-16G
or 33 when it is opened. These modifications while satisfying to
some extent the need to deliver "on demand" the hot water at the
desired 120.degree. F. to the hot water fixture valve 16A, 16C-16D,
16F-16G or 33, do so at increased capital expense and with only a
small reduction in energy costs due to the frequency when the
circulation pump 4 must be activated to satisfy the "on demand" hot
water delivery. In addition, the timer controller assembly 5 is
impractical because the time period when a hot water fixture valve
16A, 16C-16D, 16F-16G or 33 may be opened is not consistently the
same. The use of a manual or a RF control switch is also
impractical because the number of hot water fixture valves is
numerous and the capital costs to install a large number of such
switches would reduce to a great extent any energy saving achieved.
In addition limiting the number of switches then makes their use
inconvenient and still would not allow for the "on demand" delivery
of the hot water at the desired 120.degree. F.
[0035] However, it has now been found that the "on demand" delivery
of the desired 120.degree. F. hot water for washer appliances, such
as a dishwasher 17 or clothes washer 18 can be achieved with
minimal capital costs while at the same time achieving significant
reduction in energy costs. This is achieved by utilizing the
existing start or pre-wash cycle transmitted signals from the
electronic controller of the washer appliance to timely activate
and then de-activate, respectively, the hot water delivery line
circulation pump 4. This may be achieved utilizing a hard wired, RF
or other known electronic transmitter device that will transmit the
selected signals to the controller of pump 4 or to timer controller
5 that is operatively connected to the controller of pump 4. The
preferred embodiments of this invention are described utilizing a
conventional dishwasher 17.
[0036] FIG. 2 illustrates the major components of a conventional
dishwasher 17 relevant to this invention. Dishwasher 17 has an
electronic controller 20 in which at least one wash procedure
program for controlling the various cycles of the wash procedure
for the items to be washed is stored. Typically, a number of wash
procedure programs are stored in controller 20, so that by
selecting a suitable wash procedure program, the sequence of a wash
procedure directed by the controller 20 can be custom adapted to
the amount of the items loaded in the dishwasher 17 for cleaning,
the degree or type of soiling of the items and/or the desired
duration of each of the wash procedure cycles. The wash program can
in this case include at least one pre-wash cycle, at least one wash
cycle, at least one rinse cycle and at least one drying cycle. Some
dishwasher controllers have wash procedure programs that can modify
the procedure steps from temperature, turbidity and other operating
conditions during the wash procedure.
[0037] The operator of dishwasher 17 can select the desired stored
program by pressing the appropriate program activator buttons 21 on
the control panel interface 22 of controller 20, such as
illustrated in FIG. 3. The interface 22 may also include a digital
display 23 indicating the selection made by the operator or other
information.
[0038] Dishwasher 17 comprises a washing compartment 24 formed by
side and back walls 25 and a front wall 26 capable of being closed
off by a door 27. In FIG. 2, door 27 is shown in the closed
position. The door 27 is able to be moved into an opened position,
in which it is essentially aligned horizontally, by hinging it
around an axis arranged at right angles to the plane of the drawing
and which allows dishes to be loaded or unloaded. Controller
interface 22 is typically affixed to the front wall 26 or to door
27 in a position that allows the operator to easily select the
desired washing process.
[0039] Dishwasher 17 has an upper basket 28 and a lower basket 29
for holding the various items to be washed. In this case the upper
basket 28 is arranged on telescopic rails 30 which are attached to
the inside wall surface 31 of side walls 25 of the washing
container 24 in a manner that permits upper basket 28 to be pulled
out from the washing compartment 27 when door 26 is opened. The
lower basket 29 is arranged in a similar manner on telescopic rails
32.
[0040] Dishwasher 17 also includes a schematically represented hot
water feed 33 that receives hot water from hot water delivery line
15H. In this embodiment hot water feed 33 has a valve 34, such as a
magnetic valve which is able to be electronically opened and closed
by controller 20, as well as a feed hose 35. The input side of
valve 34 is embodied so that it can be attached to a connecting
member 36 of the output side of a standard water faucet 37 whose
input side is operatively connected to hot water delivery line 15H
to receive the hot water. The output side of valve 34 is connected
to feed hose 35, with its downstream end being operatively affixed
by a connecting member 38 to the back wall 39 of washing
compartment 24 to permit hot water HW flowing through valve 34 and
hose 35 to enter into washing compartment 27. In a preferred
embodiment a temperature sensor 34A is operatively positioned in
the proximity of faucet 37 to measure the water temperature of the
hot water that will flow through valve 34. Temperature sensor 34A
is embodied to transmit signals to controller 20 representative of
measured temperature.
[0041] The bottom portions of front wall 26, side and back walls
25, along with floor 40 of washing container 24 form sump 41 having
a drain area 42 in which hot water entering into washing
compartment 27 collects. Sump 41 is operatively connected to a
dishwasher water circulation pump 43 to circulate water collected
in sump 41 to a heater 44 and then to a water switch 45. Controller
20 is operatively connected to pump 43, heater 44 and to switch 45
to control their operations during the washing process. In this
illustration heater 44 is embodied as a continuous water heater,
although other known heating devices can be used to heat the water
or the air inside of the washing compartment 24.
[0042] Water switch 45 is used to direct the water (and other
cleaning compounds if present) in sump 41 to the upper rotating
spray arm 46 and the lower rotating spray arm 47 having nozzles
that direct the water spray WS into the upper basket 28 and the
lower basket 29, respectively. Further water outputs can also be
provided if desired.
[0043] To be able to control heater 44, a temperature sensor 48 is
positioned in drain area 42 to detect the temperature of the
collected water. Temperature sensor 48 is operatively connected to
controller 20 whereby a signal representative of the temperature
readings from sensor 48 is received by controller 20. Utilizing
these temperature readings, controller 20 can alter the selected
wash procedure to better ensure a more efficient cleaning of the
items in baskets 28 and 29. Similarly, a turbidity measurement
device (not shown) can also be positioned in drain area 42 to
measure the turbidity of the water in drain area 42. Likewise the
controller 20 can be operatively connected to the turbidity
measurement device to receive signals representative of the
turbidity readings, and with the use of these readings alter the
selected wash procedure to better ensure a more efficient cleaning
of the items.
[0044] Dishwasher 17 can also be provided with a dosing device 49,
typically positioned on door 27, which can be activated by
controller 20 to dispense cleaning compounds or rinsing aids into
the water collected in sump 41.
[0045] Furthermore, dishwasher 17 has a drain pump 50 that when
activated by controller 20 will drain waste water WW in sump 41 out
of the washing compartment 27 after a pre-wash cycle, a wash cycle
or a rinsing cycle via a drain valve 51 that typically directs the
water to the sewer line 52 for the home. Controller 20 is also
operatively connected to drain valve 51 to open or close drain
valve 51 depending on the amount of time that a particular cycle
has been active.
[0046] FIG. 4 illustrates what cycles a typical dishwasher
undergoes depending on whether a "heavy" or "normal" or "quick" or
"rinse" wash procedure is selected. As indicated above, the human
operator utilizing the controller interface 22 can select what wash
procedure is to be utilized by dishwasher 17. Based on the selected
wash procedure, the activation of dishwasher 17 initiates
electronic controller 20 to begin sending at predetermined time
intervals a series of program signals to the various components of
the dishwasher to permit the dishwasher to execute the programmed
pre-wash, wash, rinse and dry cycles used to clean the dishes,
glasses, cookware and other articles placed in the dishwasher for
cleaning. In this illustration the components include the water
fill valve 34, drying fans 66, water circulation pump 43, drain
pump 50, water heater 44, and soap and or water conditioner dosing
device 49. These signals are transmitted by use of an electrical
circuitry 53 such as illustrated in FIG. 5. The specifics of the
electrical circuitry 53 vary from dishwasher manufacturer and
dishwasher model.
[0047] In operation the wash procedure is first selected. In this
electrical circuitry a low voltage (12V) source 54 will deliver
power to controller 20 through low voltage DC lines 55 and 56.
However, until door switch 57 is closed by the closing of
dishwasher door 27, the low voltage DC current from controller 20
cannot flow to various solenoids 58-61 of the relays in the
electrical circuitry 53 used to control water valve 34, soap
dispenser 49, drain pump 50, drain valve 51, respectively. Once
dishwasher door 27 is closed and the controller interface start
button 62 has been pushed, the controller 20 utilizing the program
for the wash procedure selected will begin transmitting signals at
predetermined time periods to the various selected transistor
switches SW1-SW8 to close the electrical circuit to corresponding
dishwasher components and water overflow monitor to be utilized in
a particular step of the active cycle as indicated in FIG. 5.
[0048] In one embodiment of the invention, dishwasher controller 20
is operatively connected to circulation pump 4 that is operatively
positioned in hot water return line 3, and to timer 63 and
programmed when start button 62 is activated to send a first pump
signal to start pump 4 to begin circulating the water in hot water
delivery line 15 through hot water return line 3 to the hot water
heater and to initial timer 54 to for a predetermined amount of
time. After the predetermined amount of time timer 54 will transmit
a first timer signal to controller 20 that the predetermined amount
of time has expired. Controller 20 will then transmit a second pump
signal to stop pump 4. At the same time controller 20 would send a
first fill signal to valve 34 causing valve 34 to open and permit
the hot water to enter the washing compartment 24. The
predetermined amount of time is set to ensure that hot water from
line 15H will enter dishwasher 17 at the predetermined temperature,
which is typically 120.degree. F.
[0049] In an alternate embodiment of some dishwashers, the operator
may select a specific time for the wash procedure to begin by
programming a delay start time into timer 63 forming part of
controller interface 22. In this embodiment activating the start
button 62 will activate the delay timer 63 to begin tracking the
selected delay start time. When the delay start time has occurred,
delay timer 63 will send the delay time completion signal to
controller 20. Upon receipt of this signal controller 20 will
commence operation of the selected wash procedure.
[0050] In this alternate embodiment the controller program upon
receipt of the delay start completion signal will also transmit the
first pump signal to start pump 4 to begin circulating the water in
hot water delivery line 15 through hot water return line 3 to the
hot water heater 10 and to delay timer 63 to begin counting a
predetermined amount of time. After the predetermined amount of
time, timer 63 will transmit a first timer signal to controller 20
that the predetermined amount of time has been reached. Controller
20 will then transmit a second pump signal to stop pump 4. At the
same time controller 20 would send a first fill signal to valve 34
causing valve 34 to open and permit the hot water to enter the
washing compartment 27.
[0051] Depending on the controller electrical circuitry there are
other alternative electrical paths the signals can be sent and
still be within the scope of this invention. Important in this
embodiment of the invention is that controller 20 will utilize a
received signal prior to initiation of the washing cycle to start
the circulation pump 4, that the pump 4 be allowed to operate for a
predetermined period of time before it is stopped and fill valve 34
is opened.
[0052] In another alternate preferred embodiment, a temperature
sensor 64 will be operatively positioned in the hot water delivery
line 15H near the hot water feed into water faucet 37, and embodied
and operatively attached to controller 20 to send, after pump 4 has
been started, a first temperature signal to controller 20 when it
senses the hot water in line 15 has reached the predetermined
temperature. In this embodiment controller 20 would use the first
temperature signal to transmit the second pump signal to stop pump
4. At the same time controller 20 would use the first temperature
signal to transmit a first fill signal to valve 34 to cause valve
34 to open and permit the hot water to enter the washing
compartment 27.
[0053] In most normal wash procedures of a dishwasher the first
step is a pre-wash cycle. The purpose of this pre-wash cycle is to
remove the larger food particles from the items being cleaned. In
this step while it is preferred that the water temperature be at
least 120.degree. F. the use of water at that temperature is less
critical, as the dishwasher is relying on the force of water
sprayed onto the items to remove these larger food particles. The
first step in the pre-wash cycle is to open the dishwasher fill
valve 34 to permit water in the hot water delivery line to fill the
dishwasher tub or sump area 41 with a pre-determined amount of
water. A typical dishwasher will hold about 1.2-1.5 gallons of
water in its tub or sump area 41, and depending on the manufacturer
of the dishwasher this first step generally takes 40-90 seconds. At
the end of this first pre-set time period the controller 20 will
power solenoid 72 of relay 73 to connect the 110 AC circuit to wash
pump 43 that will draw the water into its intake port and from its
discharge port direct it into a water line operatively connected to
one or more spray arms 46, 47 positioned within dishwashing
compartment 27. Water from the spray arms 46, 47 will strike the
articles in the dishwasher with sufficient force to dislodge the
larger food particles from the articles. At the end of the spray
portion of the pre-wash cycle which typically takes 4-8 minutes,
the dishwasher controller 20 will send a second signal to the wash
pump 43 to deactivate the wash pump 43. It will then transmit a
third signal to a drain pump 50 and drain valve 51 to open the
drain valve 51 and to activate the drain pump 50 to remove from the
dishwasher the water and suspended food particles that has settled
back into the dishwasher tub or sump area 41. The draining of the
water and suspended food particles typically takes 40-60
seconds.
[0054] It is common that the water and suspended food particles
stream that is being pumped from the dishwasher 17 will be sent
through drain pipes to a sewer line 52. As the water and suspended
food particles leave the dishwasher it is typical in many of the
more expensive dishwashers for them to pass through a glass tube
for measurement of the turbidity of the stream by a turbidity
sensor. It is also common that that turbidity sensor 65 has an
associated tub thermistor positioned at the bottom of the
dishwasher tub to measure the temperature of the stream being
drained from the dishwasher 17. In such dishwashers a signal
representative of the measured turbidity and temperature level is
transmitted to the dishwasher controller 20 which uses this
information to determine if a second pre-wash cycle is needed to
achieve the desired level of pre-wash cleaning. In most wash
options there will be one to four pre-wash cycles.
[0055] If it is not necessary for the hot water to be at
120.degree. F. during the pre-wash cycle, then, in an alternate
embodiment, controller 20 can utilize the signals associated with
the pre-wash cycle to ensure that the hot water is at 120.degree.
F. for the next wash cycle. More particularly, controller 20 can
use the transmission of the signal transmitted to activate the
drain valve 50 and/or drain pump 51 to transmit the first pump
signal to pump 4 to start the circulation of the water in hot water
delivery line 15 back to hot water heater 10 as before. Then
controller 20 can use the transmission of any one or more of the
signals transmitted to drain valve 50 and/or drain pump 51 to close
drain valve 50 and/or stop drain pump 51. Alternatively, controller
can use the transmission of the signal to open fill valve 34 to
transmit the second pump signal to stop pump 4. It has been found
that the time period between the initiation of draining the sump
area 41 and the commencement of re-filling of the sump area 41
provides sufficient time to circulate the water in hot water
delivery line 15 back to the hot water heater 10, reheat the water
to the desired temperature, and then return the reheated water back
in hot water delivery line 15 to refill valve 34. Thus, the objects
of this invention can be achieved utilizing the already programmed
controller circuitry to provide the necessary signals to the
circulation pump 4.
[0056] The only hardware required is a simple circuit such as
illustrated in FIG. 6. In this circuit the low voltage DC (12V or
24V) line 74 is used to power solenoid 75 forming part of relay 76
to close switch 77 that completes the high voltage AC (120V)
circuit used to operate circulation pump 4. A transistor switch 78
is operatively connected to the neutral line 79 from solenoid 75.
Controller 20 would be programmed to transmit the first pump signal
to transistor switch 78 to close switch 78, and, thus, activate
pump 4 when it is desired to circulate the hot water in line 15
back to hot water heater 10. Controller 20 would also be programmed
to transmit the second pump signal to transistor switch 78 to open
switch 78 to shut off pump 4 when it is desired to stop the
circulation of hot water in line 15.
[0057] Once the pre-wash cycle or cycles are completed the
dishwasher controller will send another signal to activate whatever
mechanism 49 is used to permit the cleaning detergent to be emptied
into the dishwasher tub or sump area 41. The controller 20 will
then again activate the inlet water valve 34 to open to re-fill the
tub or sump area 41 with hot water. It is at this juncture of the
washing cycle that it is most critical that the fill water be at
120.degree. F. to ensure that the items are properly washed to
remove any oils or other material remaining on the articles to be
removed. Should it be desired that the water be at a higher
temperature a dishwasher is typically provided with heating rods or
other type heater 44 that can be used to further heat the water. At
the end of a wash cycle that, depending on the wash procedure
selected, will take 5-45 minutes, the water and suspended material
that settle back into the sump area 41 is drained. If desired more
than one wash cycle can be used in the cleaning. Once the wash
cycle or cycles have been completed, the dishwasher controller
again activates the water inlet valve 34 to refill the tub to begin
a rinse cycle that sprays the articles to remove any soap or soap
residue that are on the articles. In many cases it is desirable
that the water temperature during the rinse cycle also be at the
desired 120.degree. F. to achieve a more efficient removal of the
soap from the washed articles, as well as to maintain the higher
temperature within the dishwasher cavity for the subsequent drying
cycle. This can be achieved by using the controller signal sent to
the drain valve 51 and drain pump 50 at the end of the wash cycle
to activate the circulation pump 4, and by using the controller
signal sent to the water fill valve 34 to begin the water fill for
the rinse cycle. Again using the information from the turbidity
sensor 65 the dishwasher controller can determine if an additional
rinse cycle is necessary to obtain the desired cleaning. Once the
rinse cycles are completed, the dishwasher controller 20 activates
transistor switches SW2 and/or SW3 to complete the electrical
circuit to one or more fans 66 positioned inside the dishwasher, as
well as activates the heating rods 67 by sending electrical power
to solenoids 68 and 69 to activate the associated heater relays 70
and 71, respectively to create a hot air flow over the articles to
assist in the drying of the articles.
[0058] Although the present invention and its advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations can be made herein without departing
from the spirit and scope of the invention as defined by the
appended claims. Moreover, the scope of the present application is
not intended to be limited to the particular embodiments of the
process, machine, manufacture, composition of matter, means,
methods and steps described in the specification. As one of
ordinary skill in the art will appreciate from the disclosure of
the present invention, processes, machines, manufacture,
compositions of matter, means, methods, or steps, presently
existing or later to be developed that perform substantially the
same function or achieve substantially the same result as the
corresponding embodiments described herein may be utilized
according to the present invention. Accordingly, the appended
claims are intended to include within their scope such processes,
machines, manufacture, compositions of matter, means, methods, or
steps.
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