Note: Descriptions are shown in the official language in which they were submitted.
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AUTOMATIC BATHROOM FLUSHERS
This application claims priority from US Provisional Application 60/958,358
filed on July 3, 2007, and claims priority from US Provisional Application
60/999,591 filed on October 19, 2007.
Field of the Invention
The present inventions are directed to automatic bathroom flushers using
photovoltaic cells for supplying electrical power. The present inventions are
also
directed to automatic flushers enabling two or multiple flush volumes in
automatic
or manual modes, depending on a user action to save water during regular
operation, or provide cleaning action by increasing flush volume. The present
inventions are also directed to automatic flushers including a user interface
comprising a button and visible LEDs.
BACKGROUND OF THE INVENTION
Automatic bathroom flushers have become increasingly prevalent,
particularly in public restrooms, both for flushing toilets and urinals. Such
flushers contribute to hygiene, facility cleanliness and water conservation.
There are several types of tankless bathroom flushers on the market
including flushers supplied by Sloan Valve Company, for example, sold as
ROYAL or GEM flush valves. ROYAL flush valves may be manually
operated, or automatically operated using OPTIMA controllers and infrared
sensors. In general, bathroom flushers receive a pressurized water supply at
an
input and provide flush water at an output during a flush cycle. The flush
cycle
provides a predetermined amount of water (depending on the external water
pressure) even though there is no water tank.
In manual flushers, users initiate a flushing cycle by displacing a handle
that controls a flushing mechanism including a piston or a flexible diaphragm.
The handle movement causes a water leak from a control or pilot chamber to the
flusher's output, which lowers pressure in the pilot chamber. Due to the lower
pressure, the external water pressure lifts the flusher's piston or diaphragm
from
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a valve seat thereby enabling water flow. The stroke of the piston or
diaphragm
controls the volume of water passing through the flush valve. After some time,
the pressure in the pilot chamber increases (through a control passage)
forcing
the piston or diaphragm onto the valve seat and thus terminating the water
flow.
In automatic flushers, an object sensor initiates the flushing cycle, where
an actuator opens a relief passage enabling water flow from the pilot chamber
to
the flusher's output. This flow lowers pressure in the pilot chamber. Due to
the
lower pressure, as mentioned above, the external pressure lifts the flusher's
piston or diaphragm from a valve seat thereby enabling main water flow used
for
flushing. After the actuator seals the relief passage, the pressure in the
pilot
chamber increases forcing the piston or diaphragm onto the valve seat and thus
closing the water flow. Manual flush valves (e.g., ROYAL flush valves) may be
converted into automatically operated valves using a controller and sensor
unit,
sold under the name OPTIMA by Sloan Valve Company. Overall, the flush
valves supplied by Sloan Valve Company are durable, highly reliable, and
suitable for long-term operation.
There is, however, a need for improved automatic flushers due to a high
demand for flushers and their need in thousands of restrooms.
SUMMARY OF THE INVENTION
Embodiments of the present inventions are directed to automatic
bathroom flushers using photovoltaic cells for supplying electrical power.
Embodiments of the present inventions are also directed to automatic flushers
enabling two or multiple flush volumes in automatic or manual modes, depending
on a user action to save water during regular operation, or provide cleaning
action by increasing flush volume. Embodiments of the present inventions are
directed to automatic bathroom flushers using two or more manually activated
sensors that override the automatic operation of the flushers. The manually
activated sensors may be capacitive sensors or push buttons. Embodiments of
the present inventions are also directed to automatic flushers including a
user
interface comprising a button and visible LEDs.
The described inventions are directed to automatic bathroom flushers
using photovoltaic cells for supplying electrical power. The described
inventions
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are also directed to automatic bathroom flushers having modular design, and
methods for operating and servicing such flushers. The described inventions
are
also directed to a novel flusher cover enabling easy servicing and adjustments
and optional optimal operation.
According to one aspect, the present invention is a bathroom flusher. The
bathroom flusher includes a flusher body, a valve assembly, an electronic
control
system, and a flusher cover. The flusher body includes an inlet and an outlet,
and is designed to accommodate the valve assembly that controls water flow
between the inlet and the outlet. The valve assembly includes a valve member
movable with respect to a valve seat providing a sealing action based on
applied
pressure on the valve assembly.
According to another aspect, an automatic toilet room flusher includes a
valve including a valve body having an inlet and an outlet, and a valve seat
inside
the body. The flush valve also includes a valve member (i.e., a flush valve
mechanism) and an external cover. The valve member is cooperatively arranged
with the valve seat, wherein the valve member is constructed and arranged to
control water flow between the inlet and the outlet. The movement of the valve
member between open and closed positions is controlled by water pressure
inside a pilot chamber. The external cover is designed for enclosing an
electronic control module comprising a sensor and an actuator for controlling
operation of the flush valve. A photovoltaic cell provides electrical power.
An
optional external switch is located on the external cover for manually
triggering a
manual flush of the flush valve.
Preferred embodiments of the above aspects include one or more of the
following features: The external cover includes main cover body, a front cover
and a top cover. The front cover includes an optical window, wherein the
sensor
is an optical sensor geometrically aligned with the optical window. The main
cover body provides overall rigidity to the external cover. The individual
cover
parts of the external cover enable separate servicing and replacement of the
cover parts. The external cover includes two external switches.
The sensor may be an optical sensor and the sensor window is an optical
window. Alternatively, the sensor includes an ultrasonic sensor or a heat
sensor
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designed to detect body heat. Alternatively, the sensor is a near-infrared
sensor
that detects optical radiation in the range of about 800 nm to about 1500 nm.
Alternatively, the sensor is a presence sensor. Alternatively, the sensor is a
motion sensor.
The top cover is removable while maintaining the front cover, including a
sensor window located in place with respect to the main cover body. The flush
valve is further constructed to adjust detection sensitivity of the sensor
while
maintaining the optical window located on the main cover body.
The top cover may include at least one side surface designed for
facilitating removal of the top cover. The top cover is attached with respect
to the
valve body using at least one screw, wherein tightening of the at least one
screw
attaches the main cover body, the front cover, and the top cover to a pilot
cap
defining the pilot chamber and attached to the valve body.
The external cover may include a vent passage for venting water from
inside the external cover. The top cover includes a button constructed to move
between upper and lower positions and designed for manually triggering a flush
cycle when pushed to the lower position. The movable button includes a magnet
co-operatively arranged with a reed sensor capable of providing a signal to a
microcontroller.
The flush valve may include a piston, or a flexible diaphragm. The flexible
diaphragm includes a centrally located passage connecting the relief passage
and the outlet, wherein the flexible diaphragm is retained with respect to the
valve body by a pressure cap defining the pilot chamber. The flush valve may
include a bypass orifice in the diaphragm connecting the inlet with the
pressure
chamber, the orifice having a cross section area smaller than that of the
passage.
According to yet another aspect, in an automatic toilet flush valve
including a body having an inlet and an outlet, there is a valve assembly
located
in the body and constructed and arranged to open and close water flow from the
inlet to the outlet upon actuation signals provided by an electronic system to
an
actuator. The automatic flush valve includes a pressure cap defining a pilot
chamber in communication with the output via a relief passage controlled by
the
actuator. The automatic flush valve also includes a sensor, as part of the
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electronic system, constructed to detect a user located in front of the flush
valve
and designed to provide control signals to the electronic system, the
electronic
system being constructed to provide drive signals to the actuator. An external
cover is mounted above the pressure cap and is constructed to provide housing
5 for the electronic system. The external cover is designed cooperatively
with the
electronic system to enable sensitivity adjustment of the sensor without
removal
of the cover's sensor window.
Preferred embodiments of the above aspects include one or more of the
following features: The sensor includes an infrared sensor or an ultrasonic
sensor or a heat sensor. The sensor includes a presence sensor or a motion
sensor.
The cover is mounted above the pressure cap. The valve assembly
includes a flexible diaphragm fixed relative to the pressure cap, wherein the
valve
assembly includes a vent passage in the flexible diaphragm in communication
with the pilot chamber, being controllably sealable by the actuator.
The vent passage includes a flexible member extending between a pilot
chamber cap and the vent passage in the flexible diaphragm, wherein the
flexible
member includes a seal remaining stationary during movement of the flexible
diaphragm between open and closed positions of the flush valve. The flexible
member is a hollow tube. The hollow tube may include a spring positioned
therein. The spring may be a coiled wire.
The actuator may be an isolated actuator. The valve assembly may
include a filter for filtering water passing toward the actuator. The filter
may be
attached to the flexible diaphragm.
According to yet another aspect, a method for operating an automatic
flusher includes providing a flusher body, a valve assembly, an electronic
control
system including a microcontroller, and a flusher cover, wherein the flusher
body
includes an inlet and an outlet, and is designed to accommodate the valve
assembly that controls water flow between the inlet and the outlet, and
wherein
the valve assembly includes a valve member movable with respect to a valve
seat providing a sealing action based on applied pressure on the valve
assembly,
and executing a flusher algorithm for controlling water flow from the inlet to
the
outlet by controlling operation of the valve member.
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Preferably, the flusher algorithm controls the water volume based on the
duration of a user present in front of the flusher. For a short use duration,
the
flusher delivers a small amount of water, while for a long duration, the
flusher
delivers a larger amount of water, after the user has left the flusher's
vicinity.
This enables large water savings. The flusher algorithm also scans manual
flush buttons of the flusher to prevent extra flushes. The flusher algorithm
also
facilitates a user interface using a single or multicolor LED and one of
several
flush buttons. Upon pushing on two flush buttons, the user or operator can
initiate a large volume, longer duration flush for cleaning purposes. The
flusher
algorithm also signals to a user various error states of the flusher including
low
battery or other error conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of an automatic bathroom flusher used for
flushing a toilet or a urinal.
Fig. 2 is a perspective view of another embodiment of the automatic
bathroom flusher.
Fig. 3 illustrates diagrammatically control electronics and components
used in the automatic bathroom flusher.
Fig. 4 illustrates diagrammatically control electronics and components
used in another embodiment of the automatic bathroom flusher.
Figs. 5, 5A-I, 5A-II, 5B-I, 5B-II, 5C, 5D, 5E, 5F and 5G are circuit diagrams
that illustrate the electronics of the automatic bathroom flusher.
Fig. 6 is a circuit diagram of a capacitive sensor for detecting manual
activation of the automatic bathroom flusher.
Fig. 7 is a circuit diagram used with a photovoltaic cell mounted on the
automatic bathroom flusher.
Fig. 8 is a perspective view of another embodiment the automatic
bathroom flusher used for flushing a toilet or a urinal.
Figs. 8A and 86 are a front view and a top view of the bathroom flusher
shown in Fig. 8, respectively.
Fig. 9 is a perspective view of the bathroom flusher shown in Fig. 8,
having a flusher cover removed.
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Fig. 9A is a perspective exploded view of the flusher cover shown in Fig.
9.
Fig. 9B is a perspective exploded view of the top cover of the flusher
shown in Fig. 9A.
Figs. 9C and 9D are perspective top and bottom views of the top cover of
the flusher shown in Fig. 9A.
Figs. 10 and 10A are cross-sectional views of the flusher mainly
illustrating an electronic control module, a solenoid actuator and a flush
mechanism located inside of the flusher cover.
Fig. 11 is a perspective, partially exploded view of a circuit board located
inside the electronic control module shown in Fig. 9.
Fig. 12 is a perspective view of another embodiment the automatic
bathroom flusher having a photovoltaic cell, wherein this perspective view has
the flusher cover removed.
Figs. 13, 13A, and 13B are a front view, a perspective view and a top view
of the flusher cover shown in Fig. 12, respectively.
Fig. 14 is a perspective exploded view of the flusher cover shown in Fig.
12.
Figs. 14A and 14B are perspective views of the top cover of the flusher
shown in Fig. 12.
Figs. 14C and 14D are perspective views of a receptacle for electronics
for the photovoltaic cell.
Fig. 15 is a perspective view of another embodiment the automatic
bathroom flusher having a photovoltaic cell, wherein this perspective view has
the flusher cover removed.
Figs. 16, 16A, and 16B are a front view, a perspective view and a top view
of the flusher cover shown in Fig. 15, respectively.
Fig. 17 is a perspective exploded view of the flusher cover shown in Fig.
15.
Figs. 17A and 17B are perspective views of the top cover of the flusher
shown in Fig. 15.
Fig. 18 illustrates the flusher's operation and the individual states.
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Figs 19,19A, 19B, 19C, 19D, 19E and 19F show the overall algorithm
executed by a microcontroller.
Figs. 20 and 20A show the microcontroller timing control including
individual counters used.
Figs. 21, 21A and 21B show an internal timing tracking subroutine that
manages time-sharing for the microcontroller.
Figs. 22 and 22A show a battery power management subroutine for
monitoring a battery voltage.
Figs. 23 and 23A show an open valve timer subroutine for controlling the
flushers actuator.
Fig. 24 shows a subroutine for detecting a position of a small button used
for a manual water flush having a low volume.
Fig. 24A shown a keyboard interrupt subroutine for interrupting the
algorithm.
Fig. 25 shows a subroutine for detecting a position of a large button used
for a manual water flush having a large volume.
Fig. 26 shows a timer interrupt subroutine, which includes IR target
detection.
Fig. 26A shows a proc sensing logic subroutine that is included in the
timer interrupt subroutine shown in Fig. 26.
Fig. 27 shows a proc flush logic subroutine used for automatically flushing
after IR detection of a target.
Fig. 28 shows a stop charge subroutine used for controlling a capacitor
charging process.
Fig. 29 shows an adjust LED subroutine.
Fig. 30 shows a battery power management subroutine for monitoring
battery voltage.
Figs. 31, 31A and 31B show a subroutine for checking and controlling the
capacitor charging process.
Fig. 32 shows a charge subroutine used in the algorithm shown in Figs.
31, 31A and 31B.
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DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS
Fig. 1 is a perspective view of an automatic bathroom flusher used for
flushing a toilet or a urinal. An automatic bathroom flusher 10 includes a
flusher
body located inside enclosure 21 coupled to a water supply line 14 and also
coupled to a water output line 16 providing output to the connected toilet or
urinal. The manual embodiments of the bathroom flusher are described in U.S.
Patents 3,778,023; 5,881,993; 5,295,655, all of which are useful for
explanation
and better understanding, but are not part of the present invention. The
manual
flush valves may be converted to automatic flushers using the modules
described
below.
Automatic bathroom flusher 10 includes manual override sensors 22 and
24 used to override the flusher's sensor (e.g., an optical sensor, an
ultrasonic
sensor, a capacitive sensor, a heat sensor or a passive near infrared sensor
used for automatic operation). Preferably, manual override sensors 22 and 24
are capacitive sensors. Preferably, automatic bathroom flusher 10 also
includes
an optical window 20 used by an active or passive infrared sensor, and
includes
a photovoltaic cell 242.
Fig. 2 is a perspective view of another embodiment of an automatic
bathroom flusher used for flushing a toilet or a urinal. An automatic bathroom
flusher 11 includes a flusher body located inside enclosures 11A and/or 11B
coupled to a water supply line 14 and also coupled to a water output line 16
providing output to the connected toilet or urinal. Automatic bathroom flusher
11
includes a manual override sensor 22 (or a button as described below) used to
override the flusher's automatic sensor used for automatic operation.
Preferably,
manual override sensor 22 is a capacitive sensor. Automatic bathroom flusher
11 also includes optical window 20 and a photovoltaic cell 242 for providing
electric power.
The automatic bathroom flusher may include one, two or several
photovoltaic cells. The photovoltaic cell is mounted on the flusher cover,
preferably, behind an optically transparent window. Alternatively, the
photovoltaic cell is mounted on a frame movable relative to the flushers body.
Several photovoltaic cells may be mounted on several frames independently
movable movable relative to the flushers body. The movement can be pre-
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biased with a spring and maintained in an extended position (or depressed
inside
the cover). Alternatively, the photovoltaic cell and the corresponding frame
may
be movable as a button for manually activating the flusher (large or small
water
volume, as described below) or may be used for set up mode, diagnostics.
5 Fig. 3 illustrates control electronics 30 with a controller 32 powered
by a
battery 34. Controller 32 is preferably a microcontroller MC9S08GT16A made by
Freescale e. The microcontroller executes various detection and processing
algorithms, which are preferably downloaded. However, the controller and
algorithms may also be implemented in the form of dedicated logic circuitry,
or
10 other.
The control electronics 30 includes a power switch 35, a DC-DC converter
36, a solenoid driver 38. Solenoid driver 38 provide drive signal to a
solenoid 40
monitored by a solenoid feedback amplifier 42, and a signal conditioner 44.
Controller 32 communicates with an indicator driver 64 driving a visible diode
66
(e.g., a blue diode) for communicating with the user. The active optical
sensor
includes an IR diode driver 50 providing power to an IR transmitter 52, and an
IR
sensor amplifier 54 receiving a signal from an IR receiver 56. The entire
operation is controlled by controller 32.
The IR diode driver 50 is designed to progressively increase and decrease
the optical power output according to target and environment conditions. The
same applies to the IR receiver using IR sensor amplifier 54. Usually only one
of
the modes is used both since one is enough to achieve the purpose. The
following examples of the conditions: If the environment is too IR bright, the
system boosts the optical emission signal. If the target is too close, such as
in
the closet, the system reduces the IR signal to save power. If the target is
not
sufficiently IR reflective, the system boosts the IR signal either from the IR
transmitter 52 or using IR sensor amplifier 54.
The system uses a capacitive controller 60, which monitors sensors 22
and 24, and is shown in detail in Fig. 6. The system also uses an optional
voice
synthesizer 70 connected to a speaker for providing a user interface. An
optional
flow sensor conditioner 74 connected to a flow sensor 76 is used for detecting
water flow through the flusher. Alternatively, a sensor may be used to detect
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overflow of water in a toilet or urinal and provide signal to controller 32
for
shutting down the automatic flusher.
The system also uses an optional RF transceiver 80 connected to an
antenna 82 for wireless communication with a remotely located central
controller
or network. The present design may be deployed with a network of wirelessly
connected bathroom flushers and sanitary appliances. The remotely located
network enables monitoring and gathering of information concerning the
flushers
and appliances. The communication between the flushers and appliances uses
preferably low frequency RF signals, and the communication to the remotely
located network node uses preferably a high frequency RF signals.
In general, wired or wireless data communication is used for transmitting
information as it relates to the well being of the bathroom flushers and
sanitary
appliances. The transmitted information (together with the ID of the device)
may
include the battery voltage, number of flushes, the unit is on run-on
condition
(cannot turn off), no water condition (cannot turn on), etc. Using RF
transceiver
80 and antenna 82, the system can receive information such as command
remotely initiated from somewhere else. The fixture may talk to each other in
a
networked fashion. The fixtures may talk to a proximal central unit and the
said
unit may transmit data (wired or wireless) to a wider network such as
internet. In
preferred embodiment; the user initiates a location wide diagnostic mission by
requesting each fixture to turn on and then off. In turn, each fixture reports
successful/unsuccessful operation. The fixture may also report other variables
such as battery voltage, number of flushes, etc. The user then gathers the
information and schedules a maintenance routing according to results. This is
particularly useful in establishments such as convention centers, ballparks,
etc.
where the maintenance personnel currently send crews to monitor the well being
of the fixtures and take notes manually prior to an event.
Microcontroller MC9S08GT16A is used for the following main functions:
Microcontroller 32 manages the voltage regulation so that we deliver fixed
amount of voltage to sections of the hardware as needed regardless of the
battery voltage (DC to DC converter). Microcontroller 32 monitors manual flush
buttons. In case of capacitance touch, maintain necessary functions and
adjustments as the background of the environment changes over time.
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Microcontroller 32 monitors target by use of IR emitter and receiver circuit
and
act accordingly. Microcontroller 32 provides necessary signal to solenoid so
it
would turn on and off. Microcontroller 32 maintain self monitoring such that
if the
executable software goes to a dead loop then reset the program accordingly.
Microcontroller 32 manages all user diagnostics input. Microcontroller 32
manages all mode settings. Microcontroller 32 monitors power source levels and
take action as necessary such as close the valve and shut down operation.
Microcontroller 32 monitors solenoid latch and unlatch signals to conserve
power.
Another embodiments of the control electronics is described in PCT
Publications W02005/056938 and W02004/061343.
According to another embodiment, the control electronics includes a
microcontroller that is an 8-bit CMOS microcontroller TMP86P807M made by
Toshiba. The microcontroller has a program memory of 8 Kbytes and a data
memory of 256 bytes. Programming is done using a Toshiba adapter socket with
a general-purpose PROM programmer. The microcontroller operates at 3
frequencies (fc = 16MHz, fc= 8MHz and fs = 332.768kHz), wherein the first two
clock frequencies are used in a normal mode and the third frequency is used in
a
low power mode (i.e., a sleep mode). The microcontroller operates in the sleep
mode between various actuations. To save battery power, microcontroller
periodically samples optical sensor unit for an input signal, and then
triggers
power consumption controller. Power consumption controller powers up signal
conditioner and other elements. Otherwise, the optical sensor unit, the
voltage
regulator (or the voltage boost) and the signal conditioner are not powered to
save battery power. During operation, the microcontroller also provides
indication data to an indicator, e.g., a visible diode 66 or speaker 72.
Control
electronics may receive a signal from the passive optical sensor or the active
optical sensor described above. A Low battery detection unit may be the low
battery detector model no. TC54VN4202EMB, available from Microchip
Technology. The voltage regulator may be the voltage regulator part no.
TC55RP3502EMB, also available from Microchip Technology
(http://www.microchip.com). Microcontroller may alternatively be a
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microcontroller part no. MCU COP8SAB728M9, available from National
Semiconductor.
Fig. 4 illustrates control electronics 30A with controller 32 monitoring reed
switches 255A and 256A, activated by manual buttons 255 and 256, respectively.
Each manual button switch is formed by a reed switch, and a magnet. When the
button is pushed down by a user, the circuitry sends out a signal to the
clock/reset unit through manual signal IRQ, then forces the clock/reset unit
to
generate a reset signal. At the same time, the level of the manual signal
level is
changed to acknowledge to microcontroller 32 that it is a valid manual flush
signal.
Control electronics 30A shown in Fig. 4 uses passive optical detector
including IR sensor amplifier 90 and an IR receiver 92. The passive optical
detector is described in detail in PCT Publications W02005/056938 and
W02004/061343.
Depending on the embodiment, the flusher includes one or several
photovoltaic cells for producing voltage that is proportional to the amount of
light
that it receives. When system 30 or 30A powers up and starts operation the
system this voltage and continuously monitors the voltage thereafter. At first
time
power up, if there is no voltage from the photovoltaic cell, this means dark
environment and therefore the unit marks the time and count for a
predetermined
amount of time. It the time is long enough, such as hours and days, and there
is
no target detected within the same period of time then the flusher system is
powered up but no body is using the bathroom (i.e., the lights are turned off)
and
therefore the system goes into a power saving mode. In this mode, the system
scans for target at a much slower frequency to conserve battery power. The
system may also shut down or slow down other functions such as scanning the
override buttons, battery voltage, etc.
If there is no voltage from the photovoltaic cell, but yet the system
acquires a valid target then the system indicates an error (that is, the
photovoltaic
cell is broken or malfunctioning or the connections and/or the circuit that
relates
to photovoltaic cell is broken.) In such case the system can disable all or
some of
the functionalities related to the photovoltaic cell. These functionalities
are
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monitoring light or dark conditions of the environment, target shadow
detection,
power generation, etc.
After the first time power up, the system monitors the photovoltaic cell
function normally. In such case the module would monitor the photovoltaic cell
voltage continuously (in normal operation mode). In cases, where the output
voltage is sufficient, the system uses the corresponding energy for flushing,
or
stores the in a rechargeable device for later use. The rechargeable device may
be a capacitor or a rechargeable cell/battery. If the photovoltaic cell
voltage does
not provide sufficient power for operation, there may be a condition where the
target is casting shadow on the photovoltaic cell. In such case, the system
uses
the low voltage information as a supplement to the target detection algorithm,
whereby prior to the condition the flusher may be in slow operation mode. In
this
mode of operation, the system conserves energy. Each target is detected using
the detection algorithms (for the active or passive sensor) and the
photovoltaic
information provides a supplemental data.
If the system detects valid targets using the active or passive sensor
algorithm, and yet the photovoltaic cell voltage is low or zero over several
detection cycles, an error condition is indicated. In such case, the system
deems
the photovoltaic cell broken and ignores functionalities related to the
photovoltaic
cell, using just the battery power.
Figs. 5, 5A, 5B, 5C, 5D, 5E, 5F and 5G are circuit diagrams that illustrate
the electronics of the automatic bathroom flusher. The circuit includes a
Cypress
microprocessor CY8C21634-24LFXI which detect the capacitance touch
(proximity) sensing. The Cypress microprocessor includes an analog section
that
detects of the capacitance issues and the digital section responsible of
converting these signals to microcontroller 32 for input/output. The
capacitance
"button" may have different shapes and surfaces.
The circuit enables mode selection by use of jumper pins used to set flush
volume. The flush volume is set depending on the toilet bowl. The circuit also
uses a processor U7, which is digital trimpot used to set detection range.
Fig. 5F illustrates schematically a detection circuit 90 used for the passive
optical sensor 92 (Fig. 4). The passive optical sensor does not include a
light
source (no light emission occurs) and only includes a light detector that
detects
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arriving ambient light. When compared to the active optical sensor (using IR
light
transmitter 52 and IR receiver 56 shown in Fig. 3), the passive sensor enables
reduced power consumption since all power consumption related to the IR
transmitter is eliminated. The light detector may be a photodiode, a
photoresistor
5 or some other optical element providing electrical output depending on
the
intensity or the wavelength of the received light. The light receiver is
selected to
be active in the range or 350 to 1,500 nanometers and preferably 400 to 1,000
nanometers, and even more preferably, 500 to 950 nanometers. Thus, the light
detector is not sensitive to body heat emitted by a user located in front of a
10 flusher.
The detection circuit 90, used by the passive sensor, enables a significant
reduction in energy consumption. The circuit includes a detection element D
(e.g., a photodiode or a photoresistor), two comparators (U1A and U1B)
connected to provide a read-out from the detection element upon receipt of a
15 high pulse. Preferably, the detection element is a photoresistor. The
voltage Vcc
is +5 V (or + 3V) received from the power source. Resistors R2 and R3 are
voltage dividers between Vcc and the ground. Diode D1 is connected between
the pulse input and output line to enable the readout of the capacitance at
capacitor C1 charged during the light detection.
Preferably, the photoresistor is designed to receive light of intensity in the
range of 1 lux to 1000 lux, by appropriate design of optical lens 54 or the
optical
elements shown in PCT Publications W02005/056938 and W02004/061343.
For example, an optical lens may include a photochromatic material or a
variable
size aperture. In general, the photoresistor can receive light of intensity in
the
range of 0.1 lux to 500 lux for suitable detection. The resistance of the
photodiode is very large for low light intensity, and decreases (usually
exponentially) with the increasing intensity.
Referring still to Fig. 5F, the default logic at CONTROL IN is "high".
Comparator U1A output a "high" to node 252A. And DETECTOR READ OUT is
logic "low". Microcontroller output logic 0 from CONTROL IN; upon receiving a
"high" pulse at the input connection, comparator U1A receives the "high" pulse
and provides the "high" pulse to node A. At this point, the corresponding
capacitor charge is read out through comparator U1B to the output 7. The
output
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pulse is a square wave having a duration that depends on the photocurrent that
charged capacitor C1 during the light detection time period. Thus,
microcontroller
32 (Fig. 4) receives a signal that depends on the detected light. The CONTROL
IN is kept "low" long enough to fully discharge Cl. Then, CONTROL IN returns
to "high." Comparator U1A also follows the input, node 91A starts to charge
capacitor Cl, and comparator U1B output will turn to "high". Microcontroller
starts
a timer when DETECTOR READ OUT turns to "high". When Cl (node A) voltage
reach 2/3Vcc, U1B output will turn to "low", stop timer. The timer value (or
the
pulse width from DETECTOR READ OUT) is depends on the photocurrent. This
process is being repeated to measure the ambient light. The square wave has
duration proportional to the photocurrent excited at the photo resistor. The
detection signal is in a detection algorithm executed by the microcontroller.
By virtue of the elimination of the need to employ an energy-consuming IR
light source used in the active optical sensor, the system can be configured
so as
to achieve a longer battery life (usually many years of operation without
changing
the batteries if no photovoltaic cell is used). Furthermore, the passive
sensor
enables a more accurate means of determining presence of a user, the user
motion, and the direction of user's motion.
The preferred embodiment as it relates to which type of optical sensing
element is to be used is dependent upon the following factors: The response
time of a photoresistor is on the order or 20-50 milliseconds, whereby a
photodiode is on the order of several microseconds, therefore the use of a
photoresistor will require a significantly longer time form which impacts
overall
energy use.
Furthermore, the passive optical sensor can be used to determine light or
dark in a facility and in turn alter the sensing frequency (as implemented in
the
faucet detection algorithm). That is, in a dark facility the sensing rate is
reduced
under the presumption that in such a modality the faucet or flusher will not
be
used. The reduction of sensing frequency further reduces the overall energy _
consumption, and thus this extends the battery life.
Fig. 5G provides a schematic diagram of an alternatice detection circuit
93. This circuit may be used directly connected to the microcontroller, as
describe below. This circuit may be included into circuit 90. In Fig. 5G,
three
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resistors are connected in parallel with photodetector D. Providing VCC to
CHARGE1, or CHARGE2, or CHARGE3 at different light condition, is equivalent
to different parallel resistors connected to photodetector D. Thus, this
system can
adjust the resolution of DETECTOR READ OUT.
The microcontroller reads out optical data as follows: First, all charge pins
are set to Hi-Z (just like no Vcc, no current goes to capacitor). Then, the
input/
dicharge pin is set as output, and is set "low" so that capacitor C1
discharges
from this pin. Next, the discharge pin is charged as input. At this moment,
the
logic of this pin is "low". Then, the charge pin is set to "Hi." The
microcontroller
selects charge 0, or charge 0 +charge X (X = 1, 2, 3). Thus, the current goes
from charge 0 + chargeX to the capacitor, and at the same time the timer is
started. The capacitor voltage will increase, when it reaches 2/3 Vcc (which
is
the microcontroller power supply, and it's also I/O output voltage). At this
point
the logic in input/discharge pin will turn from "low" to "high" and the timed
is
stoped. The timer value corresponde to the charge time, which is depend on
charge current (that goes through photodetector D, and through one or several
parallel resistors). By selecting different parallel resitors and charge
together
with photocell, the timer resolution can be adjusted and the maximum charge
time can be limited.
PCT publication WO 2005/056938, provides detailed description of the
passive optical system. That PCT publication also describes various factors
that
affect operation and calibration of the passive optical system. The sensor
environment is important since the detection depends on the ambient light
conditions. That PCT publication also describes different detection algorithms
for
bathroom conditions when the ambient light in the facility changes from normal
to
bright, or from normal to dark, etc.
Fig. 6 is a circuit diagram of a capacitive sensing circuit. The circuit
includes a Cypress microprocessor CY8C21634-24LFXI, which receives signal
from one, two, or several capacitive sensors and communicates with the
Freescale microcontroller 32 shown in Fig. 3 or Fig. 4. The capasitive sensors
may be located on various surfaces of the flusher cover.
Fig. 7 is a circuit diagram of a circuit connected to photovoltaic cell.
Photovoltaic cell 240 provides electrical power at a voltage of up to 5 Volts,
which
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is charging capacitor C13. The voltage value is also provided to the
microcontroller, which assigns the highest priority to the power generated by
the
photovoltaic cell. Only if the cells voltage drops below 2.5 Volt (e.g., in a
dark
room), capacitor 33 is charged by the batteries. The solenoid driver uses
approximately 6.2 Volts for latching the solenoid and approximately 3.6 V for
unlatching the solenoid, as described below.
Fig. 8 is a perspective view of an automatic bathroom flusher for flushing
toilets or urinals. An automatic bathroom flusher 10B includes a flusher body
12
coupled to a water supply line 14 and also coupled to a water output line 16
providing output to the connected toilet or urinal. Bathroom flusher body 12
is
also coupled to a manual port 18. The manual flush valves may be converted to
automatic flushers using the modules described below. In the automatic flusher
design, manual port 18 is closed off using a cap 19 coupled to port 18 using a
lock ring 17. Figs. 8A and 8B are the respective front and top views of
bathroom
flusher 10 assembled for operation.
Automatic bathroom flusher 10B also includes an external flusher cover
enclosing electronic control module 125, shown in Fig. 9. The external flusher
cover is preferably a dome-like outer cover specifically designed for
protection
and easy servicing of control module 125. The flusher cover also includes
manual override buttons 255 and 256 used to override the flusher's sensor
(e.g.,
an optical sensor, an ultrasonic sensor, a capacitive sensor, a heat sensor or
a
passive near infrared sensor).
As shown in Figs. 8, 8A, 8B and 9, the flusher cover includes a main cover
body 100, a front cover 130, and a top cover 250. The entire flusher cover is
secured in place with respect to the flusher body using an attachment ring 122
connecting a pilot cap 134 to flusher body 12. As shown in Fig. 10, electronic
control module 125 is positioned onto an alignment plate 128, which defines
the
module's position and orientation with respect to the front of the flusher.
Electronic control module 125 includes electronic elements that control the
entire
operation of the flusher, shown in Figs. 3 and 4, including a sensor and a
controller for execution of a detection and flushing algorithm. The controller
provides signals to a solenoid driver that in turn provides drive signals to a
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solenoid actuator 40 (Fig. 10). Solenoid actuator 40 controls the operation of
the
flush valve assembly that opens and closes water flow from input 14 to output
16.
Figs. 10 and 10A are cross-sectional views illustrating flusher 10B
including electronic control module 125 and solenoid actuator 40, all located
inside of the external cover. Figs. 10 and 10A also partially illustrate the
top part
of flusher body 12 designed to receive the flush valve assembly including a
flexible diaphragm 150. Electronic control module 125 includes a water tight
housing 126 (Fig. 9), which is preferably a plastic housing, for enclosing
batteries, the electronic circuitry and a sensor. Preferably, the sensor is an
optical sensor that has a light source (i.e., a transmitter) and/or a light
detector
(i.e., a receiver) operating in the visible to infrared range. Alternatively,
the
sensor is an ultrasonic sensor or an infrared body heat detector.
Referring still to Figs. 10 and 10A, the flushing assembly includes
pressure cap (pilot chamber cap) 134, flexible diaphragm 150, and a pressure
relief assembly coupled to solenoid actuator 40. Flexible diaphragm 150
separates an annular entrance chamber 130 from pilot chamber 135, both being
located within valve body 12, wherein a bleed passage provides communication
between the two chambers. The pressure relief assembly includes a piloting
button 138 coupled to an input passage and an output passage 139 located
inside the top part 136 of pilot cap 134.
As described in the PCT application PCT/US02/38758, piloting button 138
is screwed onto the distal part of actuator 40 to create a valve.
Specifically, the
plunger of actuator 40 acts onto the valve seat inside piloting button 138 to
control water flow between the passages 139 and 143. This arrangement
provides a reproducible and easily serviceable closure for this solenoid
valve.
Co-operatively designed with piloting button 138 and actuator 40, there are
several 0-rings that provide tight water seals and prevent pressurized water
from
entering the interior of the cover. The 0-rings also seal piloting button 138
within
the chamber inside the top part 136 and prevent any leakage through this
chamber into the bore where actuator 40 is partially located. It is important
to
note that these seals are not under compression. The seat member precisely
controls the stroke of the solenoid plunger as mentioned above. It is
desirable to
keep this stroke short to minimize the solenoid power requirements.
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Referring also to Fig. 9, inside the cover, electronic control module 125 is
positioned on alignment plate 128, which in turn is located in contact with
pilot
chamber cap 134. Plate 128 includes an opening designed to accommodate top
part of pilot cap 134. Electronic control module 125 includes two circuit
boards
5 with control electronics (including preamplifiers and amplifiers for
operating the
above-mentioned optical sensor), a solenoid driver, and preferably four
batteries,
all of which are located inside plastic housing 126. The light source
associated
with electronic control module 125 is coupled to an output lens 170 providing
light
path for the emitted light. A receiver lens 172 focuses received light onto a
light
10 detector also located inside plastic housing 126. The operation of the
light
source and detector and the entire control electronics is described in the PCT
application PCT/US02/38758. Another embodiment of the optical sensor is
described in U.S. Patent 6,212,697.
Referring still to Figs. 10 and 10A, supply line 14 communicates with the
15 entrance chamber defined by valve body 12 and a chamber wall 148 formed
near
the upper end of flush output 16. Flexible diaphragm 150 is seated on a main
valve seat 156 formed by the mouth of flush output 16, and has a circularly-
shaped outer edge 154 located in contact with the periphery of pilot chamber
cap 134. Retaining ring 122 clamps pilot chamber cap 134 at its periphery 132
20 with respect to flusher body 12, wherein outer edge 154 of diaphragm 50
is also
clamped between periphery 132 and flusher body 12.
In the open state, the water supply pressure is larger in the entrance
chamber than water pressure in pilot chamber 35, thereby unseating the
flexible
diaphragm 50. When flexible diaphragm 150 is lifted off from seat 156, supply
water flows from supply line 14, through the entrance chamber by valve seat
156
into flush conduit 16. In the closed state, the water pressure is the same in
entrance chamber and in pilot chamber 135 since the pressure is equalized via
the bleed hole in the diaphragm. The pressure equalization occurs when went
passage 139 is closed by the plunger of solenoid actuator 40. Then, water
pressure in the upper, pilot chamber 135 acts on a larger surface and thus
exerts
greater force on diaphragm 150 from above than the same pressure within the
entrance chamber, which acts on a smaller, lower surface of diaphragm 150.
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Therefore, diaphragm 150 ordinarily remains seated on seat 156 (when the
passage 139 is closed for some time and the pressure equalization occurs).
To flush the toilet, solenoid-operated actuator 40 relieves the pressure in
pilot chamber 135 by permitting fluid flow between pilot entrance passage 37
and
exit passage 143. The time it takes for the chamber to refill is determined by
the
stroke of the diaphragm. Furthermore, actuator 40 controls the pressure
release
time (i.e., time for venting pilot chamber 135), which in turn determines the
time
during which the flush valve is open for water to pass. Both actuator 40 and
the
stroke of the diaphragm assembly control the duration of the flush (for a
selected
size of the bleed passage) and thus, the volume of water passing through the
flush valve. In many regions with a limited water supply, it is very important
to
closely control the volume of water that passes through the flush valve each
time
the flusher is operated. Various governments have passed different regulations
defining what water flow is permitted through a flush valve in commercial
washrooms. A novel design of the actuator and the control electronics can
deliver a relatively precise amount of flush water, as described in PCT
applications PCT/US02/38758 or PCT/US02/41576.
The design of actuator 40 and actuator button 38 is important for
reproducible, long-term operation of flusher 10B. Actuator 40 may have its
plunger directly acting onto the seat of actuator button 38, forming a non-
isolated
design where water comes in direct contact with the moving armature of the
solenoid actuator. This embodiment is described in U.S. Patent 6,293,516 or
U.S. Patent 6,305,662. Alternatively, actuator 40 may have its plunger
enclosed
by a membrane acting as a barrier for external water that does not come in
direct
contact with the armature (and the linearly movable armature is enclosed in
armature fluid. In this isolated actuator embodiment, the membrane is forced
onto the seat of actuator button 38, in the closed position. This isolated
actuator,
including button 38 is described in detail in PCT application PCT/US 01/51098.
In general, solenoid actuator 40 includes a bobbin having magnetically
wound electrical windings, and an armature linearly movable within the bobbin.
The latching versions of the actuator include a ferromagnetic pole
piece magnetically coupled to a permanent magnet acting against an armature
spring. The permanent magnet is arranged for latching the armature in the open
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state. The armature spring maintains the armature in the extended position
(i.e.,
the closed position with the plunger preventing flow through passage 37). To
flush the toilet, the microcontroller provides a control signal to a drive
circuit that
provides current to the solenoid windings of actuator 40. The drive current
generates a magnetic field that tends to concentrate in a flux path in the
ferromagnetic armature and the pole pieces as described in the PCT Application
PCT/US01/51098. The latching actuator (i.e., bistable actuator) requires no
current to keep the valve open.
In the non-latching versions, there is no permanent magnet to hold the
armature in the open position, so a drive current must continue to flow if the
pilot
valve is to remain open (i.e., the drive current is needed to hold the plunger
away
from the pilot seat allowing flow through passage 37). The pilot valve can be
closed again by simply removing the current drive. To close the pilot valve in
the
latching actuator, on the other hand, current must be driven through the
windings
in the reverse direction so that the resultant magnetic field counters the
permanent-magnet field that the actuator experiences. This allows the armature
spring to re-seat the plunger of actuator 40 in a position in which the spring
force
is again greater than the magnetic force. Then, the actuator will remain in
the
pilot-valve-closed position when current drive is thereafter removed.
Referring again to Fig. 9A, th eexternal cover is designed for optimal
operation and easy servicing of automatic flusher 10. Main cover body 100
provides overall protection and rigidity. Front cover 130 and top cover 150
have
complementary shapes with main body 100 to form a dome-like structure and to
enable easy disassembly (as shown in Fig. 9A by the exploded view). The main
body 100, front cover 130 and top cover 150 fit together like a simple three-
dimensional puzzle. In a preferred embodiment, these elements have surfaces
arranged to provide a tight water seal. As also shown in Fig. 2A, screws 160A
and 160B hold in place top cover 150 by tightening against the respective
cooperating threads 30A and 30B located in pilot cap 34. Screws 160A and
160B include respective heads 163A and 163B (Fig. 9B) optionally designed for
a unique, custom made wrench (or a screw driver head) that prevents
unauthorized removal. This arrangement holds in place and attaches together
main cover 100 with front cover 130 and top cover 150, which are all coupled
to
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the pilot chamber cover 134. This arrangement also holds control module 125
and plate 128 in place with respect to pilot cap 134, which in turn is
attached to
flusher body 12 by a retaining ring 122.
Referring to Fig. 9, main body 100 includes a side and rear surface (which
has an approximately cylindrical shape), a top surface 104, and an elliptical
abutting surface cooperatively arranged with the surface of front cover 130
shown in Fig. 9A. Main body 100 also includes an upper side abutting surface
cooperatively arranged with the corresponding surface of top cover 150 shown
in
Fig. 9A. As also described in US Patent 7,188,822, main body 100 also includes
holes cooperatively arranged with the respective screw guides for screws 160A
and 160B extending from top cover 150 to the respective threaded holes in
pilot
cover 134 (Fig. 10A). To attach front cover 130 to main body 100, main body
100 includes two slots and cooperatively arranged with lip surfaces located on
the inner side of front cover 130. The rectangular lip surfaces uniquely
define the
relative position of main body 100 and front cover 130 and provide relative
rigidity.
Main body 100 includes a divider element 119 (Fig. 10A) dividing light
sensor opening 120 into two parts. The outer side of divider 119 includes a
light
barrier, which prevents cross-talk between source lens 170 and receiver lens
172. The active optical sensor includes a light source that emits infrared
radiation focused by lens 170 through optical window 132. If there is an
object
nearby, a portion of the emitted radiation is reflected back toward optical
window
132. Lens 172 collects and provides a portion of the reflected radiation to
the
receiver. The receiver provides the corresponding signal to the
microcontroller
that controls the entire operation of the flush valve.
There is an alternative embodiment of the main body for the passive
infrared sensor, which does not include a light source, but only an infrared
detector through optical window 132. Since, in this embodiment, there is no
light
source, there is no need for divider element 119.
Importantly, the material of dome cover is selected to provide protection
for electronic control module 125 and actuator 40. The cover is formed of a
plastic that is durable and is highly resistant to the chemicals frequently
used in
washrooms for cleaning purposes. The materials are also highly impact
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resistant (depending on the type of installation, i.e., public or private) so
as to
resist attempts of vandalism. Furthermore, the flusher cover is designed to
replace main cover body 100, front cover 130, or a top cover 250 in cases of
vandalism without closing the water supply or removing electronic control
module
125. Furthermore, electronic control module 125 may be replaced without
closing the water supply.
Main body 100 can alternatively be made of a non-corrosive metal
(instead of plastic), while front cover 130 or top cover 250 are still made of
plastic. It has been found that polysulfone is a highly desirable plastic
material
for this purpose. Front cover 130 includes window 132 and can also be made of
a polysulfone plastic that does not impede or interfere with the transmission
of
infrared signals from the sensor. Preferably, window 132 masks or obscures the
interior elements in flush valve 10. Preferably, a pigment is added to the
polysulfone so that approximately 70 percent of visible light at all
wavelengths
will pass through window 132 and approximately 30 percent will be impeded. A
pigment made by Amoco bearing spec number BK1615 provides a dark (not
quite-black), deep lavender window 132, which obscures the interior
components, but yet permits transmission of a very substantial portion of
light at
the used wavelengths. Window 132 is usually made of the same material as
other portions of front cover 130, but may be more highly polished in contrast
with the somewhat matte finish of the remaining portions of front cover 130.
In
general, window 132 is made of material suitable for the selected type of the
flusher sensor.
Alignment plate 128 includes two front alignment posts, two rear alignment
posts, and two screw holes. Alignment plate 128 also includes a vent passage.
cooperatively designed with water passage 129 (Figs. 8B and 10) located in the
rear of main body 100. In the case of an unlikely malfunction, there may be a
water leak, which could create water flow into the flusher cover. Water
passage
129 provides a water outlet from inside to outside of the flusher cover. Water
passage 129 prevents water accumulation inside the flusher cover and thus
prevents flooding and possible damage to electronic module 125. Water
passage 129, however, does not allow significant water flow from outside to
the
inside of the flusher cover (e.g., from the top or the side of cover 20 during
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cleaning). This is achieved by the shaped surface of the alignment plate and
passage 129. According to another embodiment, the flusher cover 20 is
designed to withstand high pressure cleaning, while still providing vent
passage
129.
5 Importantly, the flusher cover is designed to service automatic flusher
10B
without disconnecting the water supply provided via input line 14, or removing
retaining ring 122. Top cover 250 can be removed by loosening screws 160A
and 160B and lifting top cover 150, as shown in Fig. 9A. Upon lifting top
cover
150, front cover 130 may be removed by a sliding upward motion facilitated by
10 the grooves in main body 100. Furthermore, upon removing screws 160A and
160B, the entire cover can be lifted and electronic control module 125 can be
accessed. This enables servicing or replacing electronic control module 125
while actuator 40 still remains in place and provides a seal to the external
water
supply. For example, the batteries may be replaced by removing a screw 182
15 and a back cover 181 (Fig. 10) to slide the batteries out of body 126.
After the
batteries are replaced, cover 181 is attached back and screw 182 is tightened.
Thus, the batteries may be replaced by untrained personnel without any need to
call a plumber and closing the external water supply.
Referring also to Figs. 9A, 9B and 9C, top cover 250 includes a curved
20 dome-like top surface 258 cooperatively arranged with a button retainer
270 (Fig.
9A) and buttons 255 and 256. Top cover 250 also includes side surfaces 254A
and 254B, which are functionally important for lifting top cover 150 (after
loosening screws 160A and 160B) without any tools. Top cover includes the two
buttons, which include button caps 255 and 256, magnets 257 and 258, button
25 bodies 259 and 260, and springs 290A and 290B. These elements are
constructed to ride with respect to bottom retainer 270. The control module
includes two reed switches cooperatively arranged with magnets 257 and 258.
Displacement of any one of buttons 255 or 256 displaces the corresponding
magnet 257 or 258, which is arranged to be registered by the corresponding
reed
switch 346A and 346B, shown in Fig. 11. That is, each reed switch is a sensor
sensing depression (or activation) of the flush button.
Bottom retainer 270 includes spring guides 272A and 272B for receiving
springs 290A and 290B, which are in contact with the respective button body
259
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and button body 260. Button body 259 includes protrusions 277A and 277B
cooperatively designed with recessed surfaces 278A and 278B, respectively.
Button body 260 includes a protrusion 277C cooperatively designed with a
recessed surface 278C. Bottom retainer 270 also includes attachments
openings 274A, 274B, 275A, and 275B cooperatively designed with attachment
posts 267A, 267B, 268A, and 268B, shown in Fig. 9D. The mating of
attachments openings 274A, 274B, 275A, and 275B with the corresponding
attachment posts 267A, 267B, 268A, and 268B enables connection of the bottom
retainer 270 to the horizontal surface 252 of top cover 250, while holding in
place
springs 290A, 290B, button bodies 259, 260, magnets 257, 258, and button caps
255, 256, respectively. This connection may be a snap connection, or a glued
connection, or a heat welded connection of an ultrasonically welded
connection.
A rubber cap 294 provides a water seal. Recessed surfaces 278A, 278B, and
278C of bottom retainer 270 are designed as drain openings. Rubber washers
265 and 266 are used for screws 160A and 160B, respectively. Top cover 250
includes a separator 253 for partially guiding buttons 255 and 256. Top cover
250 also includes screw guides 159A and 159B, each having a side guide for
guiding bottom retainer 270.
Importantly, the external cover is designed to adjust the sensitivity of the
optical sensor while keeping optical window 132 in place. Specifically, after
removing screws 160A and 160B the top cover 250 may be removed by holding
side surfaces 254A and 254B. The side surfaces 254A and 254B are designed
and arranged for easy removal by fingers of untrained personnel without any
need of using a specialized tool. After lifting top cover 150, the top opening
in
main body 100 provides an access port to an adjustment screw 90 (Fig. 3).
Adjustment screw 90 is coupled to an element on a circuit board 92.
A person adjusting the sensitivity of the optical sensor removes top cover
250 and also removes a seal cover 188 located on the top of controller housing
126. Below seal cover 188, there is the head of a screw that can be turned in
the
positive or negative direction to increase or decrease sensitivity of the
optical
sensor while maintaining front cover 130 and optical window 132 in place.
Specifically, according to a preferred embodiment, this screw adjusts the
resistance value of a current limiting resistor that is connected to the light
source.
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By turning in the positive direction the resistance decreases and the light
source
receives a higher drive current to increase the emitted light intensity. Thus,
the
sensitivity of the optical sensor (or an infrared sensor or an ultrasonic
sensor) is
adjusted under the actual conditions of operation. After the adjustment, seal
cover 188 is pushed back onto housing 126 to provide a seal, and top cover 250
is again attached to main cover 100 using screws 160A and 160B.
The above-described electronic control module is designed for easy and
time-efficient conversion of manual flush valves (such as ROYAL flush
valves).
The entire conversion process takes only few minutes. After the water supply
is
closed, the manual handle is removed, and lock ring 17 with cover 19 is placed
onto manual port 18. Then, the original top cover is removed from the manual
flusher body. Depending on the model of the manual flusher, the flush valve
assembly, including the flexible diaphragm, may also be replaced with
diaphragm
150 (and the flushing insert for venting the pilot chamber). Then, the entire
cover, including electronic control module 125 attached to pilot cap 134 are
screwed onto the body 12 using retaining ring 122 acting on threads 123.
As described above, the batteries in control module 125 may be replaced
without closing the external water supply. Furthermore, the entire control
module
125 may be removed and replaced without closing the external water supply.
The removed control module 125 can be sent to the factory for refurbishing,
which can even be done by untrained personnel. Furthermore, after closing the
external water supply, actuator 40 with piloting button 38 may be unscrewed
from
pilot cap 134. A new actuator and piloting button may be screwed in. The
design
of actuator 40 and piloting button 138 provide a reproducible geometry for the
plunger-seat arrangement. Thus, this design provides a reliable and easily
serviceable pilot valve.
Fig. 11 is a perspective, partially exploded view of a circuit board 300
located inside the electronic control module shown in Fig. 2. Circuit board
300
includes a receiver shroud 302, a emitter shroud 314, battery clips, a visible
LED
310, a jumper connector 320, a capacitor 322, and reed switches 346A and 346B
located to detect movement of buttons 255 and 256, respectively. Receiver
shroud 302 includes a receiver housing 304 designed for receiving a lens
located
in front of a diode detector (not shown). Emitter shroud 314 includes a
conical
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transmitter housing having a chamfer surface 316 for receiving a lens located
in
front of an IR emitter (e.g., an IR diode). The diode detector detects IR
light
reflected from a target after an emission for an IR source. Visible LED
provides
visible signals to a user regarding a state of the system (e.g., a bad battery
state). Capacitor 322 is used to provide power to the actuator for latching or
unlatching, and thus controlling the water flush, as shown in the circuit
diagram
shown in Fig. 5C. Reed switches 346A and 346B register movements of magnets
257 or 258. Jumper connector 320 receives a jumper switch for selecting
different setting of the system.
The jumper switch is used to select a particular mode such as the urinal
mode or the toilet stall mode. The jumper switch is also used to select one of
several possible flushes for a short flush, a long flush, or an increased
volume
cleaning flush. For example, in one setting, the large flush volume is 1.6
gallon
per flush and the small flush volume is 1.1 gallon per flush. In another
setting,
the large flush volume is 1.28 gallon per flush, and the small flush volume is
0.8
gallon per flush. The cleaning flush may be 10% or 20 % or larger than the
large
volume flush, depending on the settings.
Circuit board 300 also includes a trimpot 344 for adjusting the detection
sensitivity as described above. Circuit board 300 also includes alignment
posts
300A and 300B for assembly purposes. Circuit board 300 also includes battery
clips 306A, 306B, 318A, and 318B for placing batteries, and solenoid contacts
for
connecting solenoid actuator 40, shown in Fig. 10.
Fig. 12 is a perspective view of another embodiment an automatic
bathroom flusher having a photovoltaic cell 240. Similarly as shown in Figs. 2
and 9, the automatic bathroom flusher includes the flusher body coupled to a
water supply line and also coupled to a water output line providing output to
a
connected toilet or urinal. Figs. 13, 13A, and 13B are a front view, a
perspective
view and a top view of the flusher cover shown in Fig. 12, respectively. The
automatic bathroom flusher includes an external flusher cover 20A (Fig. 12)
for
enclosing the electronic control module. External flusher cover 20A is
preferably
a dome-like outer cover specifically designed for protection and easy
servicing of
the control module. Flusher cover 20A also includes photovoltaic cell 240 and
a
manual override button 216. Photovoltaic cell 240 provides electrical to the
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bathroom flusher and manual override button 216 is used to override the
flusher's sensor and activate a manual flush.
As shown in Figs. 13, 13A and 13B, flusher cover 20A includes a main
cover body 100, a front cover 130A, and a top cover 210. The entire flusher
cover 20A is secured in place with respect to the flusher body using an
attachment ring 22 connecting a pilot cap 34 to flusher body 12, similarly as
shown in Fig. 10 or 10A. The electronic control module is positioned onto an
alignment plate 28(Fig. 12), which defines the module's position and
orientation
with respect to the front of the flusher. The electronic control module
encloses
the electronic elements that control the entire operation of the flusher,
including a
sensor and a microcontroller. The microcontroller executes several detection
and flushing algorithms.
Referring to Figs. 13, 13A and 13B, all cover elements, i.e., main cover
body 100, front cover 130A, and top cover 210 have complementary shapes
fitting together so that the flusher cover forms a dome-like structure. This
structure enables easy disassembly (as shown in Fig. 14 by the exploded view).
Preferably, main body 100, front cover 130A, and top cover 210 fit together
like a
simple three-dimensional puzzle. These elements have surfaces arranged to
provide a tight water seal. Top cover 210 has an opening for mounting
photovoltaic cell 240.
As also shown in Fig. 14, screws 160A and 160B hold in place top cover
210 by tightening against the respective cooperating threads 30A and 30B
located in pilot cap 34, as shown in Fig. 3A. Screws 160A and 160B include
respective heads 163A and 163B (Fig. 3A). This arrangement holds in place and
attaches together main cover 100 with front cover 130A and top cover 210,
which
are all coupled to the pilot chamber cover 34. This arrangement restrains in
place
photovoltaic cell 240, which includes a cover 242, a photovoltaic array 244,
and a
receptacle 245 (shown in detail in Figs. 14C and 14D) for enclosing
electronics
associated with array 244. This arrangement also holds control module 25 and
alignment plate 28 in place with respect to pilot cap 34, which in turn is
attached
to flusher body 12 by a retaining ring 22 (as shown in Fig. 3A).
Referring to Figs. 12 and 14, electronic control module 25 includes two
circuit boards with control electronics (shown in Figs. 33, 33A, and 33B), a
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solenoid driver, and the batteries, all of which are located inside plastic
housing
26 similarly as shown in Fig. 10. The light source associated with electronic
control module 25 is coupled to an output lens 70 providing light path for the
emitted light. A receiver lens 72 focuses received light onto a light detector
also
5 located inside plastic housing 26. Photovoltaic cell 240 is mounted above
receptacle 245, which includes an opening 246 for the electronics associated
with photovoltaic cell 240. This embodiment may use much smaller batteries,
which may also be rechargeable. The use of some batteries is preferred but not
required since they may be replaced by another storage element. As shown in
10 Fig. 12, the control module includes contacts 248A, 248B, 248C, and 248D
providing electrical connection to the cell electronics shown in Fig. 34.
Photovoltaic cell 240 converts the energy of ambient light in the bathroom
into electrical energy. As is known in the art, upon irradiation the cell
generates
charge carriers (i.e., electrons and holes) in a light-absorbing material
using a p-n
15 junction, and the photovoltaic cell separates these charge carriers to a
conductive contact. Preferably, photovoltaic cell 240 is Sanyo AM ¨ 1815
"Amorton" with a photovoltaic layer made of amorphous silicon suitable for
indoor
applications. This cell has a size of 58.1 mm x 48.6 mm and glass thickness
1.1
mm and operates at optimized 3.0 V and 42.0 pA. Preferably, the photovoltaic
20 cell is sensitive to the visible light wavelengths ranging from
approximately
400nm to 700nm.
Alternatively, photovoltaic cells using crystalline silicon, polycrystalline
silicon, or microcrystalline silicon may be used. The photovoltaic layer may
be
made of cadmium telluride, copper indium selenide sulfide. Alternatively,
instead
25 of a traditional p-n junction, the cell may be a photo-electrochemical
cell, a
polymer cell, a nanocrystal cell, or a dye-sensitized cell. Alternatively, the
cell
may include polymers with nanoparticles can be mixed together to make a single
multi-spectrum layer and such layers are then stacked. Such cell converts
different types of light is first, then another layer for the light that
passes and last
30 is an infra-red spectrum layer for the cell.
Fig. 15 is a perspective view of another embodiment the automatic
bathroom flusher having a photovoltaic cell 240 and two manual override
buttons
235 and 236. Figs. 16, 16A, and 16B are a front view, a perspective view and a
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top view of the flusher cover shown in Fig. 15, respectively. Flusher cover
20B
includes a main cover body 100, a front cover 130B, and a top cover 230. The
entire flusher cover 20B is secured in place with respect to the flusher body
using
an attachment ring 22 connecting a pilot cap 34 to flusher body 12 (shown in
Fig.
10 or 10A). The electronic control module is positioned onto an alignment
plate
28, which defines the module's position and orientation with respect to the
front
of the flusher. The electronic control module includes contact pads 249A,
249B,
249C, and 249D located on the top surface. The electronic control module of
this
embodiment is similar as described above.
Fig. 17 is a perspective exploded view of the flusher cover shown in Fig.
15. Figs. 17A and 17B are perspective views of top cover 230 designed to
accommodate photovoltaic cell 240 and two manual override buttons 235 and
236. Smaller button 235 is used to initiate a short water flush, and larger
button
236 is used to initiate a longer water flush. Flusher cover 20B is designed to
protect control module 25 in case of water leaks as described above. Main
cover
body 100 includes water passage 128 (Fig. 4A) cooperatively designed with vent
passage 210 (Fig. 7) for venting water from inside flusher cover 20B in case
of a
water leak.
Fig. 18 shows the flusher's software, which includes the following states:
A battery check state 402, a charge state 404, a small button state 408, a
small
button sensing state 410, a large button sensing state 412, a re-power up
state
416, a latch state 422, adjust open time setting state 434, a sleep state 440,
an
IR sensing state (one pulse) 450, an IR sensing state (three pulses) 456, a
standby arm delay state 460, a standby off delay state 464, and a sleep state
440.
To save batteries, the microprocessor periodically wakes up from the
sleep state during a time base wakeup (transition 442). The wake up of the
microcontroller is 3.9 msec., 250 msec., or 1 sec depending on the algorithm.
In
battery check state 402, if no voltage on the battery is detected, or battery
voltage is less than 4.2V during a 10-minute powerup, the microprocessor goes
to sleep state 440. Alternatively, the microprocessor enters charge state 404.
During the next time-based interrupt, wake up (transition 442), the
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microprocessor starts with battery check 402. In the charge state, the system
capacitor 322 is being charged to provide power for controlling the solenoid
actuator 40.
Next, if the capacitor voltage is at least 6 V, the microprocessor transitions
to small button state 408 (transition 405). The small button is used by a user
to
activate a short flush (i.e., a small water volume flush). The large button is
used
by a user to activate a long flush (i.e., a large water volume flush). The
system
transitions to small button sensing state 410 (transition 409), and if small
button
is depressed by a user the corresponding reed switch receives a signal. If
small
button is not depressed by a user, the system transitions to large button
sensing
state 412 (transition 411). In large button sensing state 412, if large button
is
depressed and sensed for more than 350 msec, the microprocessor transitions to
latch state 422 (transition 420).
In large button sensing state 412, if large button and small button are both
pressed more than 10 sec, the microprocessor transitions to adjust open time
setting state 434 (transition 432), then continues via path 436 to sleep state
440.
If the large button is pressed for more than 30 sec, then the microprocessor
transitions to sleep state 440 (transition 421); this is used during shipping
to
preserve battery power. In this state, each wake-up only scans the large
button
to determine if shipping / storage strip 155 is still in place for shipping
and
storage purposes.
In large button sensing state 412, if no large button is pressed, or large
button is pressed from last manual active, or reaches max continual manual
active, or battery charge is less than 4.0V, or the delay is not over 5 sec
from last
active, then the microprocessor transitions from large button sensing state
412
via a transition 448 to IR sensing state 450. If in IR sensing state 450 a
target is
found, the microprocessor transitions to IR sensing state 456 (transition
454),
and if in IR sensing state 456 a valid target is found, the microprocessor
transitions to standby arm delay state 460 (transition 458). From state 450 or
state 456, if no target is found, the microprocessor transitions to sleep
state 440.
In standby arm delay state 460, if the microprocessor does not reach
target active time, than it transitions to sleep state 440. Alternatively, if
the target
moves in more than 8 sec or 12 sec after manual active, then microprocessor
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transitions to standby off delay state 464 (transition 462). The standby off
delay
state 464 leads to the automatic flush activation. The microprocessor
initiates
automatic flush actuation, that is, initiates actuator latch 422, if the
target moves
out for 2 seconds in a bathroom stall or moves out for 1 sec in the urinal
mode. If
the target is still in, or didn't reach off time, or the battery voltage is
below 4 V or
over max low battery, then the microprocessor transitions to sleep state 440
(transition 466).
The microprocessor remains in latch state 422 for 7.5 msec. From latch
state 422, the microprocessor transitions to charge state 404 (transition 426)
and
then to standby open delay state 468 (transition 407) and then to unlatch
state
upon reaching the open valve timer. The microprocessor remains in unlatch
state 472 unlatching for 7.5 msec. The microprocessor transitions then to
charge
state 404 (transition 474) and then to standby open delay state 468
(transition
407) and then to sleep state 440 via transition 469. This way the capacitor
remains fully charged. Then, again the microprocessor periodically wakes up
from sleep state 440 and transitions to battery check state 402 via time base
wakeup transition 442. Capacitor 322 maintains voltage of at least 6V.
Depending on the embodiment, the flusher includes one or several
photovoltaic cells for producing voltage that is proportional to the amount of
light
that it receives. When system 30 or 30A powers up and starts operation the
system this voltage and continuously monitors the voltage thereafter. At first
time
power up, if there is no voltage from the photovoltaic cell, this means dark
environment and therefore the unit marks the time and count for a
predetermined
amount of time. It the time is long enough, such as hours and days, and there
is
no target detected within the same period of time then the flusher system is
powered up but no body is using the bathroom (i.e., the lights are turned off)
and
therefore the system goes into a power saving mode. In this mode, the system
scans for target at a much slower frequency to conserve battery power. The
system may also shut down or slow down other functions such as scanning the
override buttons, battery voltage, etc.
If there is no voltage from the photovoltaic cell, but yet the system
acquires a valid target then the system indicates an error (that is, the
photovoltaic
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34
cell is broken or malfunctioning or the connections and/or the circuit that
relates
to photovoltaic cell is broken.) In such case the system can disable all or
some of
the functionalities related to the photovoltaic cell. These functionalities
are
monitoring light or dark conditions of the environment, target shadow
detection,
power generation, etc.
After the first time power up, the system monitors the photovoltaic cell
function normally. In such case the module would monitor the photovoltaic cell
voltage continuously (in normal operation mode). In cases, where the output
voltage is sufficient, the system uses the corresponding energy for flushing,
or
stores the in a rechargeable device for later use. The rechargeable device may
be a capacitor or a rechargeable cell/battery. If the photovoltaic cell
voltage does
not provide sufficient power for operation, there may be a condition where the
target is casting shadow on the photovoltaic cell. In such case, the system
uses
the low voltage information as a supplement to the target detection algorithm,
whereby prior to the condition the flusher may be in slow operation mode. In
this
mode of operation, the system conserves energy. Each target is detected using
the detection algorithms (for the active or passive sensor) and the
photovoltaic
information provides a supplemental data.
If the system detects valid targets using the active or passive sensor
algorithm, and yet the photovoltaic cell voltage is low or zero over several
detection cycles, an error condition is indicated. In such case, the system
deems
the photovoltaic cell broken and ignores functionalities related to the
photovoltaic
cell, using just the battery power.
Figs. 19,19A, 19B, 19C, 19D, 19E and 19F show the overall algorithm
executed by the controller. The algorithms are downloaded to the
microprocessor. Alternatively, the microprocessor functionality could be
implemented in the form of dedicated logic circuitry.
The microprocessor executes a main algorithm 500 repeatedly.
Periodically the microprocessor wakes up (step 502). In step 506, if the power
is
on RAM is cleared and initialization is performed (step 508). If the power is
off,
and the microprocessor is externally reset (step 510), the system performs
initialization, sets time-base interrupt rate according to current flag, and
sets the
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interrupt rate according to current situation (520). Then, all interrupts are
enabled (step 526). If there is un-use interrupt re-power up (step 512),
emergency initialization is performed, including reset of unused interrupt and
re-
power-up flag (step 522). Alternatively, if there is an AID error re-powerup
(step
5 514), then the microprocessor performs emergency initialization reset ND
error
re-powerup flag (step 524). Alternatively, if microprocessor is running out re-
powerup (step 516), then the microprocessor executes emergency initialization
reset running out re-powerup flag (step 526). Then, all interrupts are enabled
(step 528).
10 Referring the Fig 19A, the microcontroller executes a time base
interrupt
loop 530. Time base interrupt subroutine 530 includes a background clock
subroutine 534 (shown in Fig. 20), a time task subroutine 536 (shown in Fig.
21),
and a check battery subroutine 538 (shown in Fig. 22). In step 540, if no
sufficient battery power is detected, the algorithm terminates. Alternatively,
if AID
15 error count is larger than 100 (step 544). Then the microcontroller
clears and
resets all flags, stop charges, disables all interrupts, sets an A/D error re-
powerup flag (step 546) and re-powers up (step 504).
In step 544, alternatively, if battery voltage is less than 4.0 V (step 548)
then close valve (step 550) and go to step 552. If battery voltage is larger
than
20 4.0 V, and powerup is executed (step 552), then 10 min timer counter is
set (step
554). Alternatively, the system goes from step 552 to step 572.
In step 572, the microcontroller decides about valve opening. If the valve
opening is to be performed, the microcontroller executes a valve open timer
subroutine 570 shown in Figs 23 and 23A. This subroutine sets the flush time
for
25 a short flush, a long flush, or a cleaning flush providing increased
water volume
(compared to the long flush).
Referring to Fig. 19C, in step 574, if battery voltage is less than 4.0 V or
max flush, than perform slow charge (step 576). Alternatively, the
microcontroller
executes a check charge subroutine 578 shown in Figs. 31, 31A, and 31B. In
30 step 580, if battery voltage is less than 4.0 V, or max flush, then the
microcontroller goes to valve close (step 604), which corresponds to the
unlatch
state 472 in Fig. 18. Alternatively, the microcontroller scans small button
(step
582), and if small button pressed to execute scan small button subroutine 584
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(shown in Fig. 24), corresponding to state 410. Alternatively, the
microcontroller
executes a scan large button subroutine 590 shown in Fig 25.
If scan small button subroutine 584, or a scan large button subroutine 590
detect flush activation (step 594), a flush is executed. This flush has the
time
duration depending on the button depressed by a user. Alternatively, the sleep
flag is checked (step 598) and the system is re-powered (steps 598, 602 and
504). If the valve was just closed (step 604), the microcontroller executes
step
606. Pursuant to each latch and unlatch state, capacitor 322 is charged as
shown by transitions 426 and 474.
Referring to Fig. 19E, pursuant to step 612, if no capacitor charge is
performed (i.e., no flush due to button activation), the microcontroller
activates IR
power (step 614) and executes a timer interrupt subroutine 620, shown in Fig.
26.
Referring to Figs. 26 and 26A, the microcontroller executes a timer
interrupt subroutine 620. It stops and disables timer interrupts (step 622)
and
performs IR target detection, as shown by states 450 and 456 in Fig. 18. If a
valid target is detected, the microcontroller executes a process sensing logic
subroutine 626, as shown in Fig. 26A.
Referring to Figs. 13E and 21, next, the microcontroller executes a
process flush logic subroutine 630, shown in Fig. 27, and depicted by states
460
and 464 in Fig. 18. Prior to each flush, the time base interrupt rate is
changed to
3.9 msec for a fasted response (step 636). Pursuant to each latch, a boost
capacitor charge is executed. In step 644, if the battery is bad, the
microcontroller executes a stop charge subroutine 646, shown in Fig. 28. Next,
LED indication is provided to a user by executing an adjust LED process
subroutine 660, shown in Fig. 29. Referring to Fig. 19F, in step 654, if the
capacitor is being charged, the microcontroller enters into a wait mode (step
656). Alternatively, the microcontroller executes a check battery subroutine
670,
shown in Fig. 30. The entire time base interrupt cycle is executed again.
Figs. 20 and 20A show an internal software clock for the microcontroller
timing control. In the background clock algorithm, the 3.9 msec counter is
used
for timing the big capacitor charging period to count solenoid latch and
unlatch
interval, otherwise the 250 msec counter is use or the interrupt rate. The 1
sec
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counter is used for user timing tracking. The microcontroller power management
this way optimizes the power usage. The 1-minute counter, the 1-hour counter,
and the half-year counter are internal calendar counters.
Algorithm 500 executed by the controller includes several subroutines as
shown in Figs. 19¨ 19F. The internal timing tracking subroutine 536 (shown in
Figs. 21, 21A and 21B) manages time-sharing for the microcontroller. The
battery power management subroutine 538 (shown in Figs. 22 and 22A) is used
for monitoring of the battery voltage. The open valve timer subroutine 570
(shown in Figs. 23 and 23A) is used for controlling the flusher's actuator 40.
The
scan subroutine 584 (shown in Fig. 24) is used for detecting the position of a
small button 255 used for a manual water flush having a low volume. The scan
subroutine 590 (shown in Fig. 25) is used for detecting the position of a
large
button 256 used for a manual water flush having a large volume. The keyboard
interrupt subroutine 930 (shown in Fig. 24A) is used for interrupting the
algorithm.
The IR target detection utilizes the timer interrupt subroutine 620 shown in
Fig. 26, and this subroutine includes a proc sensing logic subroutine 626,
shown
in Fig. 26A. The adjust LED subroutine 660 (shown in Fig. 29) is used to
adjust
the LED power during the IR target detection. The proc flush logic subroutine
630 (shown in Fig. 27) is used for automatically flushing after IR detection
of a
target.
The power management uses several subroutines. The stop charge
subroutine 646 (shown in Fig. 28) is used for controlling the capacitor
charging
process. The battery power management subroutine (shown in Fig. 30) is used
for monitoring the battery voltage. The charge subroutine 578 (shown in Figs.
31, 31A and 31B) is used for checking and controlling the capacitor charging
process, and this subroutine includes a charge subroutine 1067 shown in Fig.
32.
All these subroutines are shown in the flow diagrams in great detail so that a
person of ordinary skill in this art can write the code in a selected
language.
According to another embodiment, the flush valve assembly does not
include a diaphragm, but includes a piston valve described in detail in U.S.
Patent 5,881,993. The above-described cover and control unit are also
applicable for the piston valve design. Furthermore, the above-described cover
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38
and control unit may also be used as a conversion kit for converting manual
flushers or utilizing piston valves to automatic flushers using the above-
described
conversion method.
While the invention has been described with reference to the above
embodiments, the present invention is by no means limited to the particular
constructions described above and/or shown in the drawings. The present
invention also comprises any modifications or equivalents within the scope of
the
following claims.
