Note: Descriptions are shown in the official language in which they were submitted.
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Title: A METHOD AND SYSTEM FOR CONTROLLING A NETWORK OF
WATER APPLIANCES
Field of the invention
[0002] The invention relates to a system and method for controlling a
network of appliances. In particular, the invention relates to a system and
method for controlling a network of water appliances for safer and more
efficient operation.
Background of the invention
[0003] Hot water is the leading cause of both scalds and hospital
admissions for burns. This hot water includes tap water in sinks, bathtubs and
showers. Each year approximately 3,800 injuries and 34 deaths occur in the
home due to scalding from excessively hot tap water. The majority of these
injuries involve the elderly and children under the age of five. It takes
approximately 5 minutes to produce a partial-thickness burn when exposed to
water having a temperature of 49 C but it takes less than 3 seconds when
the water temperature is at 63 C. Since infants, young children and the
elderly may not be able to respond quickly to a situation involving contact
with
hot water, maintaining water temperature below a constant safe water
temperature is essential for preventing scalds from tap water.
[0004] Serious burns and scalds require long and painful treatment.
These injuries can result in permanent scarring, physical and emotional
disability, and years of skin grafting operations. The very young and elderly
are most at risk because they tend to have a slower reaction time and/or
thinner skin.
[0005] The national building code currently allows a maximum water
tank temperature of 60 C. The organization Safe Kids Canada has worked
with the Canadian advisory committee on plumbing to develop a proposed
amendment to the national building code and the national plumbing code. The
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proposal states a performance expectation limiting the temperature of hot
water at plumbing fixtures to a maximum of 49 C.
[0006] Accordingly, there is a need for a system that can limit the
temperature of water that is provided to a water appliance (i.e. water
fixture).
It would be beneficial if the system could provide such control to a network
of
water appliances with the capability of being retrofitted to existing plumbing
systems as well as being integrated into new plumbing systems. In addition, it
would be beneficial for the system to allow many users to use the water
appliance according to their own personal preferences and provide a simple
means for the user to use the water appliance according to their preferences.
This is especially advantageous for the elderly who may have trouble
operating a water appliance in the conventional manual fashion. This is also
advantageous for elderly people who have memory or other cognitive
problems which limits their ability to use the water appliance in a safe and
effective manner. An indication of water condition is also beneficial since
the
user would then not have to test water using his/her bare skin which is an
often-used method that can lead to injury.
Summary of the invention
[0007] The invention provides a method and system for controlling a
network of appliances. In at least one embodiment, the method and system of
the invention may be used as a dynamic water controller for controlling water
appliances in a household, nursing home or other similar environment. The
water appliances may include sinks, bathtubs, showers and the like. In this
case, the appliance control system may be used to warn users of extremely
hot water conditions to prevent injury to the users. This is beneficial for
the
handicapped, elderly and young children. For instance, the system could
automatically shut down the water appliance when a maximum temperature is
approaching. The system may further include an interactive graphical
indicator for displaying water pressure and temperature along with a speaker
for announcing a water attribute, like temperature, at a particular moment in
time. Users may also be able to enter and save settings for using the water
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appliances for certain activities. The settings may include water pressure,
water temperature, water run time, and the like. An example includes, for
brushing teeth, choosing a setting of 2 minutes for letting the water run and
using 26 lbs of pressure. Another example includes selecting a temperature of
42 degrees Celsius for taking a shower.
[0008] The appliance control system may also provide dynamic water
control; for instance, dynamically controlling a water appliance so that the
water pressure is in the range of 26 to 30 psi and adjusting the water flow if
the pressure varies outside of this range. The system also enables prevention
of water-related injuries because it allows a user to set the desired water
temperature and pressure at different points of use in the house. The
appliance control system may also provide IT features for seeing how much
water is used and the amount of water that a particular user consumes.
Accordingly, the appliance control system is beneficial for the user's health,
saves energy, prevents tap water scalding and provides additional comfort at
home.
[0009] The appliance control system can be easily retrofitted to existing
inline faucets allowing for dynamic adjustment of water temperature and
pressure from a common controller. The appliance control system may also
be installed during the installation of the plumbing system while a home, and
the like is being constructed.
[0010] In one aspect, at least one embodiment of the invention
provides an appliance control system for controlling a network having a
plurality of sets of appliances. The system comprises: a control station
having
a control unit for controlling the plurality of sets of appliances and a
switch unit
for routing control signals in the network, the control station being remotely
located from the plurality of sets of appliances; a plurality of actuators
connected to the control station for receiving the control signals therefrom,
the
actuators being connected to and controlling the sets of appliances; a
plurality
of sensors, the sensors being connected to the sets of appliances for
recording information therefrom and also connected to the control station for
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providing the recorded information to the control station; and a plurality of
client stations, each client station being associated with a corresponding set
of appliances and being connected to the switch unit, each client station
being
adapted for allowing a user to make requests to the control station for using
the corresponding set of appliances.
[0011] In another aspect, at least one embodiment of the invention
provides a method for controlling a network of several sets of water
appliances, the method comprising:
(a) providing a control station including a control unit for centrally
controlling the network and a switch unit for routing control signals in the
network, the control station being remotely located from the plurality of sets
of
appliances;
(b) providing a plurality of client stations for the sets of water
appliances, a given client station being associated with one of the sets of
water appliances;
(c) providing actuators connected to the control station and the
sets of water appliances for allowing control signals from the control station
to
control the sets of water appliances;
(d) providing sensors connected to the sets of water appliances
and the control station for recording information about the sets of water
appliances and providing the information to the control station; and,
(e) providing several user accounts for one of the client stations
and several settings for one of the user accounts.
[0012] In yet another aspect, at least one embodiment of the invention
provides an appliance control system for controlling several sets of
appliances. The system comprises a control station having a control unit for
controlling the sets of appliances and a switch unit for routing control
signals
in the network, the control station being remotely located from the plurality
of
sets of appliances, wherein for each set of appliances, the system further
includes a client station associated with each set of appliances and connected
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to the control station. The client station is adapted for allowing a user to
make
requests to the control station for using at least one appliance in the
associated set of appliances. The system further includes actuators
connected to the control station and the sets of appliances for receiving
control signals from the control station to control the sets of appliances;
and
sensors connected to the sets of appliances and the control station for
recording information about at least one appliance in the sets of appliances
and providing the information to the control station. The control unit is
adapted
for providing several user accounts for a given client station and several
settings for each user account.
Brief description of the drawings
[0013] For a better understanding of the invention and to show more
clearly how it may be carried into effect, reference will now be made, by way
of example only, to the accompanying drawings which show at least one
exemplary embodiment of the invention and in which:
Figure 1 is a block diagram of an exemplary embodiment of an
appliance control system for controlling a network of appliances in accordance
with the invention;
Figure 2a is a block diagram of an exemplary embodiment of a
client station;
Figure 2b is a front view of an exemplary physical embodiment
of the client station;
Figure 3a is a flowchart of an exemplary process that may be
followed when the appliance control system is operating in USER mode;
Figure 3b is a flowchart of an exemplary process that may be
followed when the appliance control system is operating in PROGRAM mode;
Figure 3c is a flowchart of an exemplary process that may be
followed when the appliance control system is operating in MANUAL mode;
Figure 3d is a flowchart of an exemplary process that may be
followed when the appliance control system is operating in ADMIN mode;
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Figure 4a is a flowchart for an exemplary embodiment of two
control processes that may be run concurrently by the appliance control
system;
Figure 4b is a flowchart for an exemplary embodiment of a water
flow request process;
Figure 4c is a flowchart for an exemplary embodiment of an
abort water flow request process;
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Figure 4d is a flowchart for an exemplary embodiment of a client
data request process;
Figure 4e is a flowchart for an exemplary embodiment of a user
data request process;
Figure 4f is a flowchart for an exemplary embodiment of a save
user data process;
Figure 4g is a flowchart for an exemplary embodiment of a user
setting request process;
Figure 4h is a flowchart for an exemplary embodiment of an
admin data retrieval request process;
Figure 4i is a flowchart for an exemplary embodiment of a save
admin data process;
Figure 4j is a flowchart for an exemplary embodiment of a
calibration process;
Figure 4k is a flowchart for an exemplary embodiment of a
temperature monitoring process; and,
Figure 5 is a flowchart of an alternative exemplary process that
may be followed when the appliance control system includes a proximity
sensor and is operating in ADMIN mode.
Detailed description of the invention
[0014] It will be appreciated that for simplicity and clarity of illustration,
elements shown in the figures have not necessarily been drawn to scale.
Further, where considered appropriate, reference numerals may be repeated
among the figures to indicate corresponding or analogous elements. In
addition, numerous specific details are set forth in order to provide a
thorough
understanding of the invention. However, it will be understood by those of
ordinary skill in the art that the invention may be practiced without these
specific details. In other instances, well-known methods, procedures and
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components have not been described in detail so as not to obscure the
invention.
[0015] Referring now to Figure 1, shown therein is a block diagram of
an exemplary embodiment of an appliance control system 10 for controlling a
network of appliances. In this example, the appliances are water appliances
such as showers, sinks, bathtubs and the like that may be in a household, a
hotel, a nursing home and the like. However, the invention is not limited to
water appliances and may be applicable to other household appliances for
which control settings may be applied, possibly in a remote fashion, such as a
furnace, air conditioner, lights and the like.
[0016] The appliance control system 10 comprises a control station 12
having a control unit 14, a control interface 16, a switch unit 18, a memory
unit
20, an analog to digital converter (ADC) 22, a digital to analog converter
(DAC) 24, an optional external communications unit 26 and a power supply
unit 28 connected as shown. The ADC 22 and the DAC 24 may more
generally be referred to as data conversion circuitry. The control station 12
is
connected to a plurality of client stations 30a, 30b to 30N via the switch
unit
18. In one embodiment, the client stations 30a, 30b to 30N are associated
with water appliances 32a, 32b to 32N that are controlled by the appliance
control system 10. Generally speaking each of the client stations 30a, 30b to
30N is associated with a set of appliances; therefore, the water control
system
can be considered to control several sets of appliances (in some cases, a set
of appliances may include one appliance). The appliance control system 10
further includes actuators 34a, 34b to 34N and 36a, 36b to 36N and sensors
38a, 38b to 38N that are connected to the control station 12 via the DAC 24
and ADC 26 respectively. For example, the water appliance 32a may be a
shower and the water appliance 32b may be a sink in a bathroom. There may
be any number of client stations 30 and water appliances 32 in the appliance
control system 10. For simplicity of description, the client stations 30a, 30b
to
30N, the water appliances 32a, 32b to 32N, the actuators 34a, 34b to 34N
and 36a, 36b to 36N and the sensors 38a, 38b and 38N will now be referred
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to as client station 30, water appliance 32, actuators 34 and 36, and sensors
38.
[0017] The control unit 14 may be a microprocessor, microcontroller,
digital signal processor, a server or the like. The control unit 14 monitors
and
controls all inputs and outputs of the appliance control system 10. The
control
interface 16 may include a display with a graphical user interface and a
suitable input means such as a keyboard, a keypad, a mouse, and the like.
The switch unit 18 may be any suitable electronics device that is capable of
routing signals from the client station 30 to the control unit 14 and from the
control unit 14 to the actuators 34 and 36. In one embodiment, the switch unit
18 may also provide a supply voltage to power the sensors 38 and the
actuators 34 and 36. The memory unit 20 may be any suitable non-volatile
memory such as ROM or flash memory. The memory unit 20 also includes a
volatile component such as RAM, SRAM or the like for example. The control
unit 14 accepts client specific data from the various client stations 30 and
stores this data in the memory unit 20. The stored data may include water
settings, administration data, calibration data, passwords and the like.
[0018] The ADC 22 and DAC 24 may be any suitable data converter
that provide sufficient resolution and number of input/output channels. In one
embodiment of the invention, SR9300 ADCs may be used for the ADC 22.
There may be several ADCs 22 depending on the number of client stations
30. In one example, there may be two ADCs 22 that occupy two slots on the
backplane of the control unit 14 when the control unit 14 is a server. The ADC
22 receives voltage signals from the sensors 38 that provides values for at
least two features of the water appliance 32 such as water temperature, water
flow rate, water pressure, etc. For instance, in the case of temperature, an
input voltage range of 0 to 10V DC may represent a temperature range of 0 to
85 C for the water provided by the water appliance 32.
[0019] In one embodiment of the invention, SR9400 DACs may be
used for the DAC 24. More than one DAC 24 may be needed since each DAC
24 can interface with a finite number of client stations 30. For example, four
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DACs 24 may be installed in four slots of the backplane of the control unit
14.
The DAC 24, via commands from the control unit 14, is used to drive control
voltages to the actuators 34 and 36. In one exemplary case, a voltage range
of 0 to 10 V DC may be provided to the actuators 34 and 36 via the DAC 24.
In general, the control unit 14 is responsible for supplying the output to the
actuators 34 and 36 of a given client station 30 either by request from the
given client station 30 or for temperature adjustment when a particular client
station 30 is online and operational.
[0020] The power supply unit 28 may be any suitable power unit. In one
embodiment, the power supply unit 28 may be a 24 V DC power supply. The
external communications unit 26 may be any suitable electronic
communications device such as a parallel or serial port, an RS-232 port, a
USB port, a modem (including a wireless modem), and the like. The client
station 30 is custom built and provides a user interface to allow a user to
control the operation of the water appliance 32. The client station 30 also
includes a unique identifier so that the control unit 14 can identify the
appropriate water appliance 32 to apply the control signals that are received
from the client station 30.
[0021] The actuators 34 and 36 may be any suitable actuator that can
be used to control the flow of water to the water appliance 32. The actuators
34 and 36 are preferably placed inline between the hot and cold water supply
and the outlet conduit. The sensors 38 may be any suitable sensors that can
provide an indication of the current state of the water being delivered to the
water appliance 32 such as water temperature, or flow-rate. In one
embodiment, the sensors 38 may include a thermistor that may be located on
the outlet conduit of the hot and cold mixed water supply. In an alternative
embodiment, both flow-rate and water-level sensors may be included in
addition to temperature sensors. If the sensors 38 include a thermistor, such
as a suitable thermistor developed by Thermometric, then the thermistor may
be clipped-on to the discharge pipe of the water appliance to feed back
information to the control unit 14. Previous designs use a traditional
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immersion probe which must be screwed into the discharge pipe, is not
always reliable and may cause leakage problems because of the way in which
it is attached to the discharge pipe. In another exemplary embodiment, one
possible implementation involves placing similar sensors at multiple
locations.
For example, pressure sensors may be used at both the inlet and outlet of
each water appliance thus allowing the flow rate to be calculated based on the
differential of the measured values.
[0022] In one exemplary embodiment of the invention, the control unit
14 may be a server CPU such as the SR9150 processor, the switch unit 18
may be a Local Area Network (LAN) switch or an ethernet hub and the client
stations 30 can be identified via a unique IP address.
[0023] In one embodiment, an administrator may interface with the
control unit 14 via a telnet session, web browser session or via a more direct
connection.
[0024] In one embodiment, the power supply unit 28 may comprise two
24 V DC power supplies to provide power to the server, the actuators 34 and
36, and the sensors 38. Two power supplies is preferable because, the
current through the actuators 34 and 36 may fluctuate 1- 2 A which may
influence the readings obtained from the sensors 38 if the same power source
is used for both of these elements. In addition, for safety purposes, fuses
may
be provided for the actuators 34 and 36 to isolate them from the rest of the
network components.
[0025] In one embodiment, the ADC 22 and the DAC 24 may be
implemented using an appropriate ADDA. For instance, software from Z
World may be used so that the ADDA may communicate with the control unit
14.
[0026] In one embodiment, the actuators 34 and 36 may be
implemented by a proportional control solenoid valve produced by Burkert
Fluid Control System of Irvine, California, USA. These Burkert control valves
have increased efficiency and high control accuracy. These valves are simply
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installed in line with the pipes that lead to the water appliance that is
being
controlled.
[0027] In one embodiment, there may be a power coupler (not shown)
attached for each client station 30. The power coupler converts a normal
ethernet cable into a cable which can provide a supply voltage (i.e. a power
signal) from the control station 12 to the client station 30. In this case,
the
power coupler is connected between the client station 30 and the switch unit
18. Further, if a CAT5 4 twisted pair 24AWG ethernet cable is used to connect
the client station 30 to the control station 12, then an unused pair of wires
in
the CAT5 cable may be used to carry the supply voltage.
[0028] In an alternative embodiment, the appliance control system 10
may also be able to provide IT features such as gathering usage data to allow
the administrator to see how much water has been used, the amount of water
that a particular user consumes, and the like. This information may be
collected by the control unit 14 or the control unit 14 may be connected to a
PC via the external communications unit 26 so that the PC can collect this
information. The information can be used to ensure that water usage remains
at an acceptable and economical level.
[0029] The above-noted IT features may be implemented by using an
SNMP module or a suitable data acquisition software package, such as
Labview 7.0, running on a PC. A correlation between hot and cold valve
orifice opening/closing and time frame may be used to determine
consumption. For instance, applying a formula based on gallons per minute
(i.e. gpm) provides total water usage for each user on the network. For
example, letting 10V DC = 2 gpm per valve, 5V DC = 1 gpm per valve, 1.5V
DC = 0.30 gpm, and multiplying the time duration (n) with the applied voltage
to a valve provides the gallons of water that have gone through that
particular
valve if the water pressure is at 50 psi. If the water pressure is not at 50
psi,
because there is another water appliance using water in the network, then this
formula needs to be modified by the actual pressure of the water flow since
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more water has to flow in this situation to maintain the output pressure at
the
water appliance of interest.
[0030] Referring now to Figures 2a and 2b, shown therein is a block
diagram for an exemplary embodiment of the components of a client station
30 and a front view of an exemplary embodiment of the exterior of the client
station 30 respectively. The client station 30 is located near the water
appliance that is controlled by the client station 30. For instance, the
client
station 30 may be mounted on the wall inside a bathroom to control a sink,
bathtub or shower. In an alternative embodiment, the client station 30 may be
constructed so that it is waterproof and placed within the shower/bath tub
stall. In another alternative embodiment, the client station 30 may control
more than one water appliance in the same bathroom. For instance, with one
set of hot/cold actuators for the bathroom, a multi-port manifold, in this
case a
3-port manifold, may be used to control three different water control
appliances. The input to the manifold can be connected to the hot/cold
actuators while the 3 output ports of the manifold each have an on/off
controlled valve, such as a solenoid valve, under control of the control unit
14.
Each output of the 3-port manifold may be connected to one of a sink, bathtub
and shower. One of these may be on at any one time. Alternatively, two of
them may be on by providing appropriate control signals although this may
affect the output water pressure. The local user may specify which water
appliance is to be turned on via the client interface on the client station.
The
power may be supplied directly to the actuators from the local 120V AC
source.
[0031] The client station 30 includes a client processor 42, a client
memory unit 44, a display 46, a client interface 48, a data port 50 and a
supply regulator 52 connected as shown. The client station 30 may further
include an optional buzzer 54. The client processor 42 may be any suitable
microprocessor or a digital signal processor and the client memory unit 44
may be any suitable memory device. The display 46 may be an LCD that
displays alphanumeric characters as well as symbols to indicate various
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conditions such as whether the water is hot or cold. Accordingly, this
information may be displayed numerically or graphically. For instance, a
symbol may be displayed on the display 46 to indicate whether the water is
too hot and/or too cold. For this purpose, the client station 40 may also
include the buzzer 54 which can provide an audible warning when certain
hazardous conditions occur. In one embodiment, the client station may be
implemented via an OP6800 MiniCom with the keys being modified for the
functions described herein.
[0032] The display 46 may include several fields to provide information
so that a local user can interface with the client station 30. For example, as
exemplified in Figure 2b, the display 46 may include a mode field 56 and a
description field 58. In other embodiments, there may also be an
information/performance field (not shown) to provide information on
performance or other general information as well as text received in an email.
The mode field 56 provides a description of the current mode of operation for
the client station 30. The description field 58 provides an explanation of
which
keys to use and the effect of using those keys for the given mode of
operation. For instance, as exemplified in Figure 2b, given manual mode of
operation, the description field 58 may tell the local user to use the arrow
keys
on either side of the cold indicator "C" on the keypad to increase or decrease
the amount of cold water that is provided to the water appliance 32. The
description field 58 may also tell the local user to use the arrow keys on
either
side of the hot indicator "H" to increase or decrease the amount of hot water
that is provided to the water appliance 32.
[0033] The client interface 48 may be any suitable data input means. In
one exemplary embodiment, the client interface 48 may include a keypad 60
having several touch keys 64 to 76 and an LED field 62 having several LEDs.
The keypad 60 includes a cold decrease touch key 64 and a cold increase
touch key 66 that can be used to decrease and increase, respectively, the
amount of cold water that is provided to the water appliance 32. The keypad
60 further includes a hot decrease touch key 68 and a hot increase touch key
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70 that can be used to decrease and increase, respectively, the amount of hot
water that is provided to the water appliance 32. The touch keys 64 and 66
may be colored in light blue, or another suitable color, to indicate that
these
keys control the amount of cold water that is provided to the water appliance
32. The touch keys 68 and 70 may be colored in red, or another suitable
color, to indicate that these keys control the amount of hot water that is
provided to the water appliance.
[0034] It should be noted that the keys 64, 66, 68 and 70 may also be
used to make numerical entries. For instance, the keys 64, 66, 68 and 70 may
also represent the numbers 1 to 4, respectively, and can be used to enter
passwords, select answers identified with numerals for multiple choice
questions, provide numerical information, and the like.
[0035] The keypad 60 further includes mode keys 72 and 74 that may
be used to provide YES and NO answers to various questions that are posed
by the control station 12. The mode keys 72 and 74 may also be used to
provide an increase or decrease, respectively, in the amount of a particular
feature related to the operation of the water appliance 30, such as the
duration of time for which water is provided to the water appliance 30. The
mode keys 72 and 74 may also be used to select a particular local user or
setting. For instance, the local user may be identified by a number from 1-9
and it is important for the local user to identify themselves because
different
settings may be programmed for different users. The mode keys 72 and 74
may also be pressed together to toggle between different modes of operation.
[0036] The keypad 60 further includes an OFF key 76 that is used to
turn off the flow of water to the water appliance 32 and to return the client
station 30 to an idle state. To start the flow of water to the water appliance
32,
either of the touch keys 66 and 70 may be used. The OFF key 76 also
provides an enter functionality that can be used by the local user to enter a
selection or answer to a question. In general, the display 46 shows the user
setting and two keys: the touch key that must be pressed in order to access
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the setting, and a second touch key that has to be pressed to make the water
flow.
[0037] The LED field 62 may be used to provide information about the
water that is being provided by the water appliance 32. Firstly, when the
client
station 30 is in operation, various LEDs in the LED field 62 may be lit. For
instance, the LEDs may blink a certain color, such as yellow for example,
when the control station 12 is adjusting the water provided by the water
appliance 32 to a desired preset temperature. In a variation, the number of
LEDs that are lit may increase as the temperature of the water reaches a
desired preset temperature if one was set. The LEDs may also turn a constant
color, such as green, when the desired temperature has been reached. This
indicates that it is okay for the local user to use the water appliance 30.
The
LEDs may also blink another color to indicate that the temperature is too hot.
For instance, if the water is above 60 C, then there is a danger of scalding
so
the LEDs may blink another appropriate color to indicate danger, such as red
for example. The LEDs may also blink at another rate for different situations.
In addition, when the appliance control system is operating in ADMIN mode,
an administrator may program the red LED indicating scalding to turn on when
a pre-set temperature threshold, which may be set in degrees Celsius or
Fahrenheit, is reached.
[0038] The data port 50 provides a connection between the client
station 30 and the control station 12. The data port 50 may be any suitable
data connection means that interfaces with the control station 12. For
instance, if the control unit 14 is a server and the switch unit 18 is a LAN
switch or Ethernet hub then the data port 50 may be an Ethernet port. In this
case, a CAT5 4 twisted pair 24AWG ethernet cable may be used to connect
the client station 30 to the switch unit 18. In other embodiments, the data
port
50 may be a USB port or an RS-232 port. In another alternative embodiment,
a wireless link may connect the client station 30 to the control station 12.
In
this case, appropriate wireless components such as wireless transceivers
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may be used to facilitate the wireless interface between stations 12 and 30 as
is commonly known by those skilled in the art.
[0039] The supply regulator 52 receives a supply voltage and provides
this supply voltage to the various components of the client station 30, via
the
client processor 42, to power up the client station 30. The supply regulator
52
may also process the supply voltage, in ways that are commonly known to
those skilled in the art, so that the supply voltage is suitable for use with
the
components of the client station 30. The supply regulator 52 may receive the
supply voltage from the data port via the ethernet cable as described above.
Alternatively, the supply regulator 52 may be directly connected to an
electrical outlet to receive a supply voltage.
[0040] In an alternative embodiment, the appliance control system 10
may be interfaced to a computer system so that the appliance control system
10 may receive messages such as email messages which can be accessed
by a local user. For instance, the appliance control system 10 may receive an
email and then route this email to the appropriate client station 30. The
client
station 30 may then indicate that there is a received email message by
providing a suitable indication, such as picture of an envelope, on the
display
46. The local user may then use the client interface 48 to indicate that
he/she
wishes to read the email message. Security information may also be received
from a security system in the building and displayed on the display 46.
[0041] In use, a user can interact with the appliance control system 10
in a number of different ways. In a first case, the user may interact directly
with the client station 30 to control the water appliance 32 directly. In a
second
case, the user may interact with the control station 12 to control a water
appliance 32 remotely. In both cases, the user may also set several control
settings for the water appliance 32 in which, for each setting, the local user
may specify values for certain parameters such as a maximum flow rate,
maximum temperature and the like. The user may be able to save up to
several number of settings such as 6 settings for example. In another case,
different settings may be set depending on who uses the client station 30.
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This may be set by a "supervisory" user or an administrator at the control
station 30 and then a local user who uses the client station 30 may enter an
identification code with the client station 30 to be able to access control
settings that may have been set just for that particular local user. The
various
modes of operation for the appliance control system 10 will now be described
in further detail. In general, several user accounts can be provided for each
client station and each user account may include several settings for a given
user.
[0042] The appiiance control system 10 may be configured to
accommodate a certain number of client stations 30. Once an initial number of
client stations 30 is selected then the appropriate amount of hardware may be
added to the control station 12 such as several ADCs 22 and DACs 24, an
appropriate number of client stations 30, actuators 34 and 36 and sensors 38,
and a switch unit 18 that can accommodate all of the client stations 30.
Advantageously, the appliance control system 10 is scaleable. Accordingly, if
more client stations 30 are added to the appliance control system 10, more
hardware components are added as needed. For instance, the embodiment
which uses IP addresses easily allows for scaling the number of client
stations, and associated hardware, in the appliance control system 10. When
a client station is added to the network, an IP address is coded into the
client
station. Further, production servers may be equipped with DHCP capability
with each client station receiving its IP address from the DHCP server when
the client station is connected to the LAN switch. Also, the local AC voltage
that is closest to the water appliance, when adapted properly, may be used to
supply operating voltage to the actuators that are used with the water
appliance. In a further alternative, wireless client stations can be
wirelessly
connected through a wireless network access point which would eliminate all
direct cable runs to the LAN switch.
[0043] As an example, the appliance control system 10 may be initially
configured to accommodate 20 client stations 30. Each of the client stations
30 is given a unique identification or address so that the control station 12
can
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contact an intended client station 30 to send control instructions or other
information. The address also lets the control station 12 know which client
station 30 is sending information. In the exemplary ethernet network
implementation of the invention, each of the client stations 30 may be
provided with a unique IP address and the control station 12 is also given a
unique IP address. The IP address may be hard-coded via a client software
program that is saved in the client memory unit 44 and loaded into the client
processor 42 during operation. Alternatively, the IP address may be
configured by a suitable hardware means on the client station 30 such as via
a DIP-switch and the like.
[0044] Data for the operation and configuration of the appliance control
system 10 is stored in the memory unit 20 of the control station 12. A data
backup allows the data to persist even if supply power is removed from the
appliance control system 10. The battery may be provided as part of the
control unit 14. The appliance control system 10 may use passwords for
allowing certain users to use the water appliances 30 and to configure the
operation of the appliance control system 10. Accordingly, there may be
several user passwords and administrator passwords. The user password
may be a numerical value and can be related to the numbers that can be
entered at the client station 30. For instance, in the example described
herein,
the local user may enter the numbers 1, 2, 3 or 4 and the user password may
consist of a sufficient number of these numerals; for example six digits.
There
may be some more flexibility for the administrator password since a full
keyboard may be used as part of the control interface 16. The administrator
may customize the passwords as well as other settings for the appliance
control system 10.
[0045] Prior to operation, default settings may be used which the
administrator may change. For instance, the default setting may be the
MANUAL MODE of operation and USER PASSWORDS may be set to ON.
This means that local users must enter a password at the client station 30 in
order to use the water appliance 32. Alternatively, if USER PASSWORDS is
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set to OFF, then anyone may use the water appliance 30 without having to
enter a password. Another part of the default setting can be the type of water
appliance (i.e. fixture) that the client station 30 is connected to. For
instance,
fixture = 1 may indicate a bathtub, fixture = 2 may indicate a sink and
fixture =
3 may indicate a shower. The control unit 14 can then treat each fixture type
differently and use a different control algorithm in a dynamic state when the
water pressure is lowered throughout the network of water appliances.
Usually, showers are given the highest mean value. A water appliance will be
given a higher priority depending on the effect of a change in water pressure
or water temperature for a local user when another water appliance suddenly
turns on. This is true because there is one water source that is providing
water to each water appliance that is on. Accordingly, in some cases, some
water appliances may not be allowed to turn on if there is already too much of
a load on the network and some high priority water appliances are already on.
[0046] The water control system 10 includes several modes of
operation such as a USER mode, a PROGRAM mode, a MANUAL mode and
an ADMIN mode. Appropriate graphics, information and instructions may be
displayed on both the control interface 16, which may include a computer
monitor and the like, and the display 46 of the client station 30.
[0047] The USER mode allows local users to log in and select a pre-
configured appliance setting such as the amount of hot and cold water that is
to be used and the amount of time for which the water appliance 32 should be
on. Controlling the amount of hot and cold water that is provided to the water
appliance 30 also has an effect on the amount of water pressure delivered for
the water appliance 30 since mixed hot and cold water creates a pressure
which becomes an attribute of temperature. For example, increasing the DC
control signal to the actuator that controls the amount of hot water provided
to
the water appliance will increase temperature and pressure (i.e. 0 V DC is
equivalent to 0 psi and 10 V DC is equivalent to 50 psi). The USER mode only
responds to the information that has been entered into the system while in
PROGRAM mode.
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[0048] The PROGRAM mode allows existing local users or new local
users to configure a number of control settings for the water appliance 32 as
well as set a password. The MANUAL mode allows the local user to operate
the water appliance 30 without having to enter a password or choose a
setting. In this mode, the local user may simply control the water appliance
via
a "digital interface" whereas conventionally people interact with water
appliances via an analog means; i.e. by turning knobs or lifting and partially
rotating levers. The ADMIN mode allows the administrator to configure
settings for the appliance control system 10. For instance, the administrator
may select settings for a particular client station 30 such as whether MANUAL
mode is available, the amount of water that can be used, etc. The ADMIN
mode is accessed with an appropriate password.
[0049] When a new water appliance and associated client station is first
commissioned into the network, an administrator may use the ADMIN mode to
set the different attributes for that station such as an identification
number, a
mean priority number and the like. PROGRAM mode may then be used by the
users of the client station to enter programmed settings that are stored in
the
memory unit 20 to be used and recalled on demand. The USER mode can be
used for the day-to-day usual operating mode of the new client station that
provides the user of the new client station to use single digit entry, in one
example, to recall a preconfigured setting from the control station 12.
MANUAL mode allows the user to directly control the new water appliance
from the client station to turn water flow on and off.
[0050] Referring now to Figure 3a, shown therein is a flowchart of some
exemplary steps that may be followed in a user mode process 80 when the
appliance control system 10 is operating in USER mode. In step 82, the local
user can select a user ID using the -/+ touch keys 72 and 74 or the touch keys
64 to 70 and then the touch key 76. In step 84, the local user may then have
to enter a password, if it is required, using the touch keys 64 to 70 and then
the touch key 76. In step 86, the local user can then select a water setting
by
using touch keys 64 to 70 or touch keys 72 and 74 and then the touch key 76.
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In step 88, after OFF has been pressed or the time expires if a certain
duration was selected for providing water to the water appliance 32, the
process 80 returns to step 82.
[0051] Referring now to Figure 3b, shown therein is a flowchart of some
exemplary steps that are followed in a program mode process 90 when the
appliance control system 10 is operating in PROGRAM mode. In step 92, the
local user can select a user ID as described previously. In step 94, the local
user may then have to enter a password, if it is required, as described
previously. In step 96, the local user can change their password. In step 98,
the local user can configure a water setting by selecting a water setting
number, and adjusting the hot and cold water flows until desired levels are
reached using the touch keys 64 to 70, and then accepting the water flow for
the current setting by using the touch key 76. The local user may then select
the amount of time for which water should be provided to the water appliance
30 by using the touch keys 72 and 74 and then selecting the touch key 76. In
step 100, the local user may configure another water setting in which case the
process 90 goes to step 98. Various water settings may be made for each
local user based on what the local user is doing. For instance, given a water
sink appliance, the local user may select different settings for shaving,
washing their face, brushing their teeth, etc.
[0052] For instance, in PROGRAM mode, for a family that includes a
father and mother with 4 children named John, Judy, Bill and Kim, the main
bathroom sink could be configured with the following: Father (local user 1),
Mother (local user 2), John (local user 3), Judy (local user 4), Bill (local
user
5) and Kim (local user 6). The father may have three user settings to record
water temperature and pressure for various activities. For instance, setting 1
may be used to brush teeth using moderately cold water for 2 minutes (this
may translate to a control voltage of 1 to 3 V DC on the appropriate
actuator).
Setting 2 may be used to wash hands using a combination of moderately hot
and cold water for 20 seconds. Setting 3 may be used to shave using
maximum hot water to half fill the sink for 10 seconds. The Mother and
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children could make similar settings according to their preferences. When the
Father goes to the bathroom to brush his teeth, the display on the client
station 30 will ask him to select a user number. Once the Father enters his
user number, the client station 30 will then ask him to enter the desired user
setting. If the Father enters setting 1, the cold water will run for 2 minutes
and
then turn off.
[0053] Referring now to Figure 3c, shown therein is a flowchart of some
exemplary steps that may be followed in a MANUAL mode process 110 when
the appliance control system 10 is operating in MANUAL mode. In step 112,
the local user can turn on the water appliance 32 and adjust the water
settings
using the touch keys 64 to 70. In step 114, the local user uses the water
appliance for its intended purpose. In step 116, the local user then turns off
the water appliance by using touch key 76.
[0054] Referring now to Figure 3d, shown therein is a flowchart of some
exemplary steps that may be followed in an ADMIN mode process 120 when
the appliance control system 10 is operating in ADMIN mode. In step 121, the
administrator enters a password as described previously. It should be noted
that if there is more than one administrator then the first step may also
include
selecting an administrator ID. In step 122, the administrator may change their
password. In step 123, the administrator may allow manual mode for a
particular water appliance 30 or may allow manual mode on a global basis
(i.e. for all water appliances in the appliance control system 10). In step
124,
the administrator may choose whether the local user requires a password to
operate a particular water appliance 30. The administrator may also decide
that user passwords are required on a global basis. In step 125, the
administrator enters a fixture order. The order provides the control unit 14
with
a priority order in terms of which water fixture provides first service in
case of
contention in the dynamic process of water adjustment. For instance, the
order may be: 1) bathtub, 2) sink 3) shower and 4) other. Providing the
fixture
order or priority control feature is one way of ensuring personal safety for
someone using a water appliance associated with a given client station. For
CA 02509019 2006-04-04
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example, a person taking a shower may be given priority over a person
washing their hands in a basin. The priority control feature may be
implemented based on a number plan from 1-4 with 4 being the highest
priority for an example with four water fixtures associated with a client
station.
This priority control feature can be executed at msec speeds with a focus on
the safety of the water appliance users.
[0055] In step 126, the administrator has the ability to set many
parameters for the appliance control system such as the maximum hot water
setting, the maximum cold water setting, the maximum number of settings
available to a local user, the range for the time duration setting (one
example
is 0 to infinite), the maximum number of local users per client station (for
example 10), and Comm retries (this means that an error occurred in the
system 10 during communication but the control unit 14 will try to complete
the message a certain number of times). In step 127, the administrator may
then perform calibration on a given water appliance to calibrate the readings
that are provided by the sensors associated with the given water appliance
(an exemplary calibration method is described below). The administrator can
then exit the administrator process 120 in step 128.
[0056] The appliance control system 10 may provide calibration of
water temperature at each water appliance, independently of each other using
a built in software routine to offset pipe distribution length. The local user
enters the desired water temperature at the client station in degrees Celsius.
The calibration program which is run as part of system
integration/initialization
then computes an adjusted desired water temperature so that the actual water
temperature at the water appliance will be similar to that desired by the
local
user. For instance, some water appliances may be 300 hundred feet from the
water source and so there will be some fluctuation in the temperature of the
water once it reaches the water appliance. This can be taken care of by
calibrating the appliance control system 10 in ADMIN mode as follows. First
the control station sends control values to the actuators of the client
station to
provide water at a first calibration temperature at the client station such as
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25 C. A person at the water appliance can then see the actual temperature,
measured by a temperature probe attached to the outlet of the water
appliance near the thermistor. The person then uses the manual hot and cold
keys on the client interface 48 to drive the actuators so that the actual
water
temperature at the water appliance is, or is acceptably close to, the first
calibration value. The person then informs the control station 12 that the
first
calibration temperature has been reached. The next step is that the control
station 12 drives one of the actuators to its maximum value which provides a
second calibration temperature that is measured by the temperature probe.
This second calibration temperature is then sent by the person to the control
station 12 and stored. This process may also be automated by having the
control station 12 directly communicate with the temperature probe. The
advantage of this feature is that pipe length and diameter is not a
consideration.
[0057] Another way in which calibration may be done is to have the
control unit 14 run a calibration program in the following fashion: cold water
is
first run and the temperature of the cold water is measured at the water
appliance via the corresponding sensor. The measured temperature in
degrees Celsius is then stored in the memory unit 20 of the control unit 14.
The hot water is then run and the temperature of the hot water is measured.
The second measured temperature in degrees Celsius is then stored in the
memory unit 20 of the control unit 14. This calibration may be done in ADMIN
mode. By applying many different control signals to the actuators and
recording the actual temperature, the control unit 14 may construct a look-up
table that is stored in the memory unit 20 and used to provide a desired
temperature at a particular water appliance when requested by a local user.
[0058] A network control program operates on the control unit 14 to
control the operation of the appliance control system 10. Referring now to
Figure 4a, shown therein is a flowchart for an exemplary embodiment of an
information retrieval process 130 and a message retrieval process 140 that
may run concurrently on the control unit 14. In step 132 of the
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information retrieval process 130, the control program reads all of the data
from the sensors 38. In step 134, the control program converts the measured
data into the appropriate units. For instance, if values related to
temperature
are provided by the sensors 38, then the raw voltage values are preferably
converted to degrees Celsius. In other embodiments, other types of data may
be read depending on the type of sensors that are used. The information may
then be stored in step 136. This is one way in which the control unit 14
calibrates the control signals provided to the actuators when various water
appliances are on in the system 10. This allows the control unit 14 to
simulate
different load cases in which different water appliances are on at the same
time and compensate by applying appropriate control signals to the actuators.
In the "wired" server-based embodiment, the Control unit 14 has the ability to
balance the entire network of water appliances mainly due to the speed of the
networked connections (i.e. ethernet connections) and processor speed at
each client station and by monitoring each pre-set thermistor value at
suitable
programmable rate, such as 500 msec, and then nudging the different
actuators that require change to keep within their user preset limits.
[0059] In step 142 of the message retrieval process 140, the control
program checks to see if a client message has been received from one of the
client stations 30. If a client message has not been received, then the
process
140 remains in step 142. However, if a client message has been received,
then the process 140 moves to step 144 in which the client message is
processed. A particular process is then followed depending on the type of
client message. The various types of client messages may include water flow
request, abort water flow request, configure a water setting, etc. While the
message is being handled in step 144, the process 140 still checks to see if
messages are received from other client stations. The sensors are wired
directly to the ADCs and so collisions for data measurements will not occur,
nor will collisions for control signals since the actuators are wired directly
to
the DACs. If there is a collision based on more than one client station
communicating with the control station, then according to the network
protocol, the messages may be retransmitted a certain number of times.
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[0060] Referring now to Figure 4b, shown therein is a flowchart for an
exemplary embodiment of a water flow request process 150. In this case, one
of the local users requests water flow for a water appliance via the
appropriate
client station in step 152. In step 154, the control program calculates the
appropriate control voltages for the corresponding hot and cold water valve
actuators and sends the control signals to the actuators. In step 156, the
control program sends an acknowledgement to the client station.
[0061] Referring now to Figure 4c, shown therein is a flowchart for an
exemplary embodiment of an abort water flow request process 160. In this
case, one of the local users originally requested water flow for a water
appliance and then changed their mind. Consequently, an abort water flow
request message is sent via the appropriate client station in step 162. In
step
164, the control program sends control signals to the actuators to close the
hot and cold water valves for the water appliance of interest. In step 166,
the
control program sets the client status to OFFLINE. In step 168, the control
program sends an acknowledgement to the ciient station.
[0062] Referring now to Figure 4d, shown therein is a flowchart for an
exemplary embodiment of a client data request process 170. In this case, one
of the local users requests information about a water appliance. The
information may be water temperature, water flow rate, water pressure, water
run time, and the like. The request may also be more general; for instance,
inquiring about water consumption for the water appliance over a set period or
for the entire network of water appliances for a certain time period. In step
172, the client makes a request for temperature data, in this example. In step
174, the control program responds with the requested information which the
client station displays to the local user.
[0063] Referring now to Figure 4e, shown therein is a flowchart for an
exemplary embodiment of a user data request process 180. In this case, one
of the local users requests information regarding information about the user
that is stored in the system 10. For instance, this information may include
how
many settings have been programmed for the user, how much water has
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been used by the user, etc. In step 182, the user makes a request for user
data. In step 184, the control program responds with the requested user data
which the client station displays to the user.
[0064] Referring now to Figure 4f, shown therein is a flowchart for an
exemplary embodiment of a save user data process 190. In this case, some
of the information that is entered by the local users is saved in the memory
unit 20. In step 192, the user sends user data to the control unit 14 which is
to
be saved. In step 194, the control program stores the user settings. In step
196, the control program sends an acknowledgement to the client station.
[0065] Referring now to Figure 4g, shown therein is a flowchart for an
exemplary embodiment of a user setting request process 200. In step 202, the
control unit 14 receives a request from a client station 30 to select a
particular
user setting. In step 204, the control program provides control signals to the
hot and cold water valve actuators to ensure that the valves are set to the
preconfigured settings. In step 206, the program sets the client status to
ONLINE to indicate that the corresponding water appliance is on.
[0066] Referring now to Figure 4h, shown therein is a flowchart for an
exemplary embodiment of an admin data retrieval request process 210. In
step 212, the control unit 14 receives a request from a client station 30 to
retrieve administration data. In step 214, the control program provides the
administration data to the client station. This process may occur in which a
local user programs some values for some settings and then requests the
administrator to provide these values so that the local user can double-check
that the correct values were entered for the settings.
[0067] Referring now to Figure 4i, shown therein is a flowchart for an
exemplary embodiment of a save admin data process 220. In step 222, the
control unit 14 receives a message to save administration data from a client
station. In step 224, the control program stores the administration data in
the
memory unit 20. In step 226, the control program sends an acknowledgement
to the client station.
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[0068] Referring now to Figure 4j, shown therein is a flowchart for an
exemplary embodiment of a calibration process 230. In step 232, the control
unit 14 receives a calibration request from a client station in which the
client
provides a first data point generically referred to as X which represents the
number of data points sent to the control program during calibration (i.e. on
the first transmission X is 1, on the next transmission X is 2). In step 236,
the
process 230 determines whether the data point X is the first or second data
point. If the data point X is the first data point then the process moves to
step
236 in which it is assumed that the sensor is sensing room temperature (since
no water has been flowing) and the process 230 sets a value for a parameter
which represents the nominal thermistor resistance R25 (it is assumed that a
thermistor is used for the temperature sensor) and stores the value for the
parameter R25 in the memory unit 20 in step 240. This value is the actual
value provided to the ADC 22. However, if it is determined that the data point
X is the second data point in step 234, then the process 230 moves to step
238 in which the process 230 calculates the thermistor's material constant R
from the temperature reported by the thermistor, the thermistor's nominal
resistance R25, and the current thermistor resistance value. The thermistor's
material constant p is then stored in the memory unit 20 in step 240. For an
NTC (Negative Temperature Coefficient) thermistor, the current temperature
(T) can be calculated according to equation 1:
T = 298=R/(298=In(Rt/R25)+P)-273 (1)
in which P is the thermistor's material constant in Kelvins, Rt is the current
thermistor resistance in Ohms, and R25 is the thermistor's nominal resistance
at 25 C. Rearranging equation 1 provides a way to obtain P according to
equation 2.
R = ((T+273)=(298=In(Rt/R25))/(25-T) (2)
An acknowledgement may then be sent to the client station 30 in step 242 to
signify that the control unit 14 has calibrated the temperature sensor
associated with the client station 30.
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[0069] Referring now to Figure 4k, shown therein is a flowchart for an
exemplary embodiment of a temperature monitoring process 250. In step 252,
the process 250 determines whether the temperature reading is stable for a
particular water appliance. If the process 250 determines that the temperature
is stable, then the process 250 moves to step 254, where it determines
whether the particular client station is online. If the client station is
online, then
the process moves to step 256 where it determines whether the temperature
is within an acceptable range with respect to the desired water temperature
that is requested by the local user. In step 258, the process 250 determines
whether the desired temperature has been reached for this water appliance or
whether the temperature sensor has "warmed-up" for this water appliance;
"warmed-up" means whether the temperature sensor is at room temperature.
A delay may be used to provide the temperature sensor with enough time to
stabilize to the water temperature. If either of these events are true, then
the
process 250 moves to step 260 in which the process 250 determines what the
temperature status is which is the amount of deviation of the temperature of
the water from the desired temperature. If the temperature is too hot, the
process 250 moves to step 262 in which the control program directs the cold
actuator to open the valve in the cold water pipe up to a MAX setting if
needed and decrease the size of the valve opening in the hot water pipe
down to a MIN setting if needed. The process 250 then moves to step 264 in
which the process 250 monitors the water temperature to see if it is
decreasing. If the water temperature is decreasing, then the process 250
moves to step 252. However, if the water temperature is not decreasing, after
a suitable elapsed time such as the elapsed time to provide 10 to 20 control
values to the actuator, the process 250 moves to step 266 in which the
process 250 sets the status for the client station 30 to NO COLD WATER and
the current user setting is then aborted. The process 250 then moves to step
252.
[0070] Alternatively, if the process 250 determined that the temperature
is too cold in step 260, then the process 250 moves to step 268 in which the
control program directs the hot water actuator to open the valve in the hot
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water pipe up to a MAX setting if needed and decrease the size of the valve
opening in the cold water pipe down to a MIN setting if needed. The process
250 then moves to step 270 in which the process 250 monitors the water
temperature to see if it is increasing. If the water temperature is
increasing,
then the process 250 moves to step 252. However, if the water temperature is
not increasing, after a suitable elapsed time such as the elapsed time to
provide 10 to 20 control values to the actuator, the process 250 moves to step
272 in which the process 250 sets the status for the client station 30 to NO
HOT WATER and the current user setting is then aborted. The process 250
then moves to step 252.
[0071] In process 250, priority is given to the client station that has a
water appliance that is on that is given the highest priority number if more
than one client station experiences a change in temperature. This is important
since, a priority number per client station can be devised and used to address
dynamic water supply when water is supplied from a common hot/cold water
supply. This does not impact on the safety of the system 10 since control
signals can be provided on the order of milliseconds to provide control in
real-
time.
[0072] The temperature monitoring and adjustment is preferably
continually performed by the control unit 14 for each operational client
station
based on input from the sensors associated with the operational client
stations. The control unit 14 takes the appropriate action based on the
circumstances; one example of which was shown in Figure 4k. The current
temperature may be calculated from equation 1 provided above for NTC
thermistors. The control unit 14 may use the temperature information to
provide status codes to one of the client stations as needed and/or to take
necessary actions (as exemplified in Figure 4k). Some exemplary status
codes include:
OFFLINE: The client station has no running water.
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OK: The water temperature is stable and within the required
range (i.e. the programmed value +/- an allowed variance) for
the user's setting.
PENDING: The water temperature is not within the required
range. Adjustments to the water flow may be made at this time.
During the PENDING state, adjustments to the hot/cold valves
may be made by the control unit 14 to attempt to return the
water temperature to the required value as exemplified in Figure
4k.
WARNING: The water temperature has reached a dangerous
level and scalding is a possibility.
NO HOT WATER: Attempts to increase the water temperature
are having no effect, and it is possible that the hot water supply
has been cut off.
NO COLD WATER: Attempts to decrease the water temperature
are having no effect, and it is possible that the cold water supply
has been cut off.
[0073] In another alternative embodiment of the appliance control
system 10, the sensors 38a ... 38N now include a proximity sensor that may
be preferably installed near the water output of a particular water appliance.
The proximity sensor allows a user at the client station to wave his/her hand
close to the water appliance to activate the water appliance for a particular
setting. This allows a user to activate a given water appliance associated
with
a given client station in a non-touch fashion. The control unit 14 is adapted
to
store operational parameters for operating the given water appliance when
activated in a non-touch fashion. The option to use a proximity sensor and the
particular setting that it activates can be controlled from the control unit
14 as
explained below. Using the proximity sensor to activate a particular setting
can be advantageous for certain situations such as for medical personnel who
need to vigorously wash their hands to remove any possible germs. In this
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case, the medical personnel do not need to touch the water appliance,
thereby preventing the spread of germs, and can have the water appliance
preprogrammed to provide a higher water pressure for more effectively
cleaning his/her hands.
[0074] Referring now to Figure 5, shown therein is a flowchart of an
alternative exemplary process 300 that may be followed when the appliance
control system 10 includes a proximity sensor and is operating in ADMIN
mode. Process 300 is similar to process 120. However, process 300
accommodates the use of proximity sensors. Step 302 of process 300 allows
the administrator to select whether proximity sensors are enabled for a given
client station. Step 304 then allows the administrator to set proximity
settings
for the users who use the given client station. For instance, the
administrator
can set values for water parameters when the proximity sensor is enabled
such as water temperature, water pressure and the like. These settings may
also be associated with a particular user id. The user may be able to identify
themselves through non-touch means such as voice activation for instance so
that their settings are applied to the water once they interact with the
proximity
sensor.
[0075] A simulation of the operation of the appliance control system 10
was performed. To simulate the I/O structure, two potentiometers were tied to
a 9V battery and used to mimic the temperature inputs for first and second
client stations, and a set of two DC voltage meters were used to read the
values of the control signals that would have been given to the valve
actuators for the first and second client stations. In addition, the
programming
port on the server CPU was connected to a PC to give additional textual
output showing all communications between the client stations and the server.
[0076] Four tests were performed. Test #1 was done to determine if a
water appliance 32 could be controlled remotely in which a water temperature
and water running time was set. Test #2 was done to determine if a water
appliance 32 could be dynamically adjusted. Test #3 was done to determine if
the system 10 can send and receive data to and from more than one client
CA 02509019 2005-06-02
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station 30 without any collision or contention. Test #4 was done to determine
if the system 10 displays a warning message and turns off a water appliance
32 if the water at that water appliance gets too hot.
[0077] In Test #1, an administrator configured the first client station to
operate with a 50% cold water flow rate and a 50% hot water flow rate for a
duration of 30 seconds. The user setting was initiated on the first client
station
by pressing the appropriate touch key that selected setting #1 and then
pressing the enter touch key 76. The voltage meters then each read 5 V DC
which corresponds to the control voltages that are provided to each of the hot
and cold valve actuators. This provides a flow rate of 50% for the cold and
hot
water since the voltage range of the control signal that is provided to the
hot
and cold valve actuators is 0 to 10 V DC. Accordingly, 10 V DC is equivalent
to maximum valve flow rate and 0 V DC is equivalent to no flow in this
exemplary test.
[0078] Once the water began to flow, the first potentiometer was at its
lowest setting which corresponds to a temperature reading of 1 C. This
temperature reading was shown on the display 46 of the first client station.
The LED field 62 started blinking yellow to indicate that the control system
10
was adjusting the water to the first water appliance. The first potentiometer
was then slowly increased until 15 C was shown on the display 46 of the first
client station. After a few seconds, the LED field 62 was no longer blinking
yellow and solid green was displayed along with a message that "water is
OK". Approximately thirty seconds after the green light was displayed, the
first
client station turned off and the voltage meters dropped to 0 V. All control
voltages to the actuators were then set to OV DC. Accordingly, in one
embodiment, the run duration for the water is measured from the time that the
water reaches the desired temperature.
[0079] In Test #2, an administrator configured a first setting for a first
local user on the first client station to have an infinite time duration while
the
flow rates remained the same as they were from Test #1. The first local user
logged into the first client station and initiated the first setting. The
voltage
CA 02509019 2005-06-02
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meters both then indicated a reading of 5 V DC for the hot and cold flow rate
valve actuators. The first potentiometer was initially at the lowest setting
and
the temperature reading on the display 46 of the first client station was 1 C.
The LED field 62 started blinking yellow to indicate that the control system
10
was adjusting the water to the water appliance. The first potentiometer was
then slowly increased until 10 C was shown on the display 46 of the first
client
station. After a few seconds, the voltage meters began to swing, with the
voltage meter representing the cold water flow valve actuator decreasing and
the voltage meter representing the hot water flow valve increasing by
approximately 0.4 V DC at intervals of approximately 1 second. When the
meter representing the cold water flow valve actuator reached 0 V DC and the
meter representing the hot water flow valve actuator reached 10V, all activity
was stopped. The first potentiometer was then increased until 20 C was
shown on the display 46 for the first client station. After a few seconds, the
voltage meters began to swing in the opposite fashion, with the voltage meter
representing the cold water flow valve actuator showing a higher voltage
reading and the voltage meter representing the hot water flow valve actuator
decreasing by approximately 0.4 V at intervals of approximately 1 second.
This interval of 0.4 V, which corresponds to a valve movement of a few
degrees, provides quite accurate and repeatable water flow rate and
temperature changes at the water appliance. Depending on the valve
actuator, and the temperature swing that must occur, the control signals to
the
actuator may vary by more or less than 0.4 V. When the meter representing
the cold water flow valve actuator reached 10 V DC and the meter
representing the hot water flow valve actuator reached 0 V DC, all activity
was
stopped. The OFF button was then pressed (since the default run time was
set to infinity) and the voltage meters provided a reading of 0 V. This test
shows that the values that are provided by the sensor are used to adjust the
control voltages that are sent to the actuators depending on the network water
usage.
[0080] In Test #3, an administrator configured the first setting for the
first local user on the second client station to have a hot water flow rate of
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75 l0, a cold water flow rate of 25%, a final temperature of 40 C and an
infinite water running time. The settings remained the same on the first
client
station as they were in Test #1. The first setting on the first client station
was
then initiated. The voltage meters both then provided a reading of 5 V DC for
the hot and cold flow rate valve actuators for the first water appliance. The
first setting on the second client station was then initiated. The first and
second potentiometers were at the lowest setting and the temperature reading
on the display 46 of the first and second client stations both showed 1 C. The
first and second client stations both showed that water was being adjusted at
the same time; i.e. the LED fields 62 for both client stations started
blinking
yellow. The first potentiometer was then slowly increased until 14 C was
shown on the display 46 of the first client station. After a few seconds, the
LED field 62 was showing a solid green color and the message that the "water
was OK" was shown on the display 46 of the first client station.
[0081] During this time, the second potentiometer was also slowly
increased until 41 C was shown on the display 46 of the second client
station. After a few seconds, the LED field 62 was showing a solid green color
and the message that the water temperature was OK was shown on the
display 46 of the second client station. This demonstrates that the appliance
control station 12 exhibits an acceptable deviation of +/- 1 C. Further, the
testing showed that both client stations were receiving temperature readings
from the control unit 14 every 2 seconds (this interval may be adjusted). The
Off touch keys were then pressed for both client stations and the system 10
returned to the idle state. The test showed no signals of slowdown or server
contention as a result of both clients being online at the same time.
[0082] In Test #4, an administrator configured the first client station to
operate with a 50% cold water flow rate and a 50% hot water flow rate for a
time duration of 30 seconds. The voltage meters then each read 5 V DC for
the hot and cold flow valve actuators. The first potentiometer was then
increased until 60 C was shown on the display 46 of the first client station.
A
scald warning then appeared on the display 46 and the LED field 62 started
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blinking with a red color. The OFF button was then pressed and the readings
from the voltage meters reduced to 0 V DC. The scald threshold value was 60
C in this case, but this threshold value can be set to any desired level by
the
administrator. When this occurs, the actuators are provided with a control
signal of OV DC (i.e. the valves are closed).
[0083] Accordingly, in one embodiment the control unit 14 may be
configured to perform a complete shutdown of both the hot and cold valves
when a programmed temperature is reached at a given client station 30. The
control unit 14 simply requires the identification number for the given client
station 30. Further the display 46 of the "offending" client station 30 may
display the message "SAFETY SHUTDOWN".
[0084] Alternatively, in another embodiment, when a maximum
temperature is reached, the actuator corresponding to the hot water valve can
be given a control signal to close the hot water valve while the actuator
corresponding to the cold water valve can be given a control signal to
increase the opening in the cold water valve to provide enough cold water to
reduce the temperature of the water below the scald threshold to a safe value.
The converse applies when a low minimum temperature is reached.
[0085] Some elements of the invention such as the programs that are
run by the client processor 42 and the control unit 14 may be implemented via
a computer program which may be written in C, C++, LabviewTM or any other
suitable programming language. The control program may be saved in the
memory unit 20 and may include a client program module that provides the
functionality of the client station and a control program module that controls
the overall operation of the control system 10. These programs are typically
executed at the client station 30 and control unit 14, respectively. These
computer program modules comprise computer instructions that are adapted
to perform the steps of the various processes that are described herein. The
computer program may comprise other modules or classes, as is known to
those skilled in object oriented programming, that are implemented and
structured according to the structure of the processes. In one embodiment,
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separate software modules or classes may be designed for each of the
processes. Alternatively, the functionality of these components may be
combined into a smaller number of software modules where appropriate.
Further, in another embodiment, the LABVIEWTM software package may be
used for implementation purposes. In this case, various LABVIEWTM software
tools can be used for measurement and control purposes. The LABVIEWTM
software package may also be used to develop a GUI interface at the level of
the control unit 14 with which an administrator may interact to monitor the
appliance control system 10. In one case, the GUI interface may be
implemented as a touch interface/screen at the control unit 14.
[0086] The system 10 of the invention uses a common piece of
equipment, i.e. the control station 12, to control and balance a complete
network of fixtures. Also, the system 10 uses less hardware compared to prior
devices. All parts in the system 10 are also UL/CSA/CE compliant. The
embodiment of the invention which uses an Ethernet structural framework
enables remote access for monitoring and controlling the network of
appliances plus the ease for service and increasing the network size without
overloading or bringing down the network. Further, the Ethernet allows other
IP based services to be easily added to the system 10 which includes water
metering, hot water usage records, SNMP control, etc. In addition, the control
unit 14 uses a mean priority number per client station to address the dynamic
water supply issue from a common hot/cold water supply. A client station with
a higher mean priority number will take priority over a client station with a
lower mean priority number in instances where the control unit must send
control voltages to actuators associated with these two different client
stations
at the same time. In addition, in one embodiment, the actuators, which may
be electronic proportional solenoid valves, are the only active mechanical
part
of the system 10 which increases the robustness of the system 10 to
mechanical failure.
[0087] The system of the invention may be used in heath care
institutions, nurseries, senior living communities, and various buildings such
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as hotels, homes and the like. Any environment may use the invention in
which there is a need for a person to set and maintain constant tap water
temperature and pressure in order to prevent hot water scalding and thermal
shock as well as to allow a person to remotely read the current values of
pressure/temperature from interactive display. Pressure may be controlled
based on the user settings submitted to the control station 12 for a given
client
station. For instance, when a temperature change is effected at a water
appliance, actuators change the water flow rate which has an effect of
increasing or decreasing pressure at the water appliance. In this fashion, the
control station 12 can monitor pressure values at various water appliances.
[0088] It should be understood that various modifications can be made
to the embodiments described and illustrated herein, without departing from
the invention, the scope of which is defined in the appended claims.
