Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: ELECTRONIC MODULE FOR CONVENTIONAL
PARKING METER
FIELD OF THE INVENTION
The present invention relates to parking meters, and more
particularly, it relates to an electronic module attachable to a conventional
parking meter, for providing that conventional parking meter with features
of modern electronic parking meters.
BACKGROUND OF THE INVENTION
Parking meters in general permit vehicles to be parked along a street
for an allowable period of time, which is determined by the amount of
money inserted therein. A mechanical clockwork or electronic timer inside
the parking meter runs down the allowable time until it reaches zero time,
and causes an overdue parking indication to appear through a window of
that meter. In recent years, parking meters have been improved greatly by
the development of low powered electronic circuitry, ultrasonic trans-
mitters and receivers, and wireless communication systems.
Revenues from parking meters are normally used by municipalities
to cover the ever-increasing costs of maintaining its infrastructure in a good
condition. Therefore the improved modern meters are attractive for a
municipality for increasing the revenues generated from its metered parking
systems.
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A first example of modem parking meters is disclosed in U.S. Patent
5,454,461 issued on Oct. 3, 1995 to James P. Jacobs. The electronic
parking meter described therein includes; means for detecting and deter-
mining the denomination of coins, a liquid crystal display having a digital
time counter, a sonar transducer for detecting the presence of vehicles, and
an infrared transceiver enabling parking authority personnel to commu-
nicate with the meter. The meter is operated in three conditions including
an off condition, an inactive condition and an active condition to provide
conservation of power so that the meter is entirely battery operated.
Electronic parking meters having these described features are
especially attractive to municipalities because all time expiry conditions
thereof are readily communicated to parking authority personnel via a
central computer. The parking authority personnel may thereby be
effectively dispatched to those vehicles in violation of parking rnles, to
issue parking tickets to the owners of those vehicles. Such improvement
of a metered parking system is known to increase revenues from those
meters considerably.
Other examples of modern electronic parking meters are solar
powered and also have liquid crystal displays, for displaying advertisement
messages to users of metered parking spaces. -These particular meters are
disclosed in U.S. Patent 5,442,348, issued on Aug. 15, 1995 to Joshua
Mushell, and in U.S. Patent 4,872,149 issued on Oct. 3, 1989 to Gary W.
Speas. Hence, another source of income for a municipality having
electronic parking meters is generated from the sale of advertising
messages displayed on the liquid crystal displays of the meters, to
businesses located near the metered parking spaces.
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The replacement of a quantity of conventional mechanical meters
with newer electronic models represents, nonetheless, a substantial
investment of funds for the purchase of the electronic units, an investment
of manpower time and wages for replacing the conventional meters by the
electronic models, and a financial loss in the writing-off of the
undepreciated value of the conventional meters. Therefore, in a period of
budget restraint as during the present times, the acquisition of electronic
meters is not economically feasible for many municipalities.
As an alternative to an entire replacement of conventional parking
meters by electronic units, a number of retrofit electtonic devices exists to
enhance the operation of conventional parking meters. Such a unit mounts
adjacent to a conventional parking meter, and connects to the clockwork of
the meter. A first and second examples of these controllers are described
in U.S. Patent 3,535,870 issued on Oct. 27, 1970 to Harold B. Mitchell,
and in U.S. Patent 3,999,372, issued on Dec. 28, 1976 to Welch et al.
The controller of the first example or the control unit of the second
example, comprises an ultrasonic transmitter and a receiver to detect the
presence of a vehicle near a standard parking meter. Once the vehicle
leaves the parking space, the meter is automatically returned to zero time
such that a next vehicle cannot take advantage of the remaining time credit
of the meter. In the first case, the controller is connected inside the meter
to a mechanical switch, and has a solenoid for resetting the clock hand to
a zero time position. Similarly, in the latter example, the control unit is
connected to a pair of solenoids and a pair of mechanical switches mounted
inside the meter head.
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The installation of the retrofit units of the prior art requires intensive
modifications to the clockwork of conventional parking meters. These
modifications are usually better done by the original manufacturer of the
meters. Therefore, the upgrading of a quantity of conventional meters with
the retrofit units represents also a substantial investment in manpower time
and wages to remove and send the meters to the manufacturer, and to
reinstall the modified meters. Other expenses include the cost for
modifying the clockwork, and the lost of revenue from the parking system
when substitutable meters are not available to replace those meters
removed for alteration.
SUMMARY OF THE INVENTION
In the present invention, however, there is provided an electronic
module for enhancing an operation of a conventional parking meter having
at least one of a time expiry indicator and a violative condition indicator.
The electronic module of the present invention comprises a shell
defining a hollow conformation and having mounting means attachable to
a conventional parking meter, and a first sensor affixed to that shell for
detecting from a distant point the indicator of that conventional parking
meter, when the shell is mounted on this conventional parking meter and
when the indicator is in an indicating mode.
The electronic module also comprises a second sensor affixed to the
shell for detecting from a distant point, a vehicle parked in a parking space
at proximity of the conventional parking meter when that shell is mounted
on the conventional parking meter.
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The electronic module further has an electronic circuitry mounted
inside the shell and having a power source for operating the module. The
electronic circuitry has means for receiving a first signal from the first
sensor and a second signal from the second sensor, for processing the first
and second signals, and when appropriate, for transmitting a coded message
to a remote receiver. The coded message comprises at least an identi-
fication relative to a location of the conventional parking meter.
A first advantage of this first aspect of the present invention is that
the electronic module is mountable on a conventional meter without
modification or attachment to any of the internal components of the
conventional parking meter. An installation of the electronic module over
a conventional parking meter is thereby effected quickly and without tools,
at the parking meter location.
Hence, a municipality managing conventional parking meters having
each an electronic module of the present invention mounted thereon has the
ability to generate more revenue from these conventional meters. A
municipality managing the enhanced conventional meters has a better
control over the metered parking system due to the fact that when a parking
meter is in a time expiry condition or in a condition of violation, the coded
message is transmitted to a remote receiver at the municipality headquarters
for example. A law enforcement officer or metered parking attendant may
thereby be effectively dispatched to a location of that parking meter to
write and issue a parking ticket to the owner of the vehicle in the parking
space.
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Another advantage of the electronic module of the present invention
is that a municipality managing an array of conventional parking meters
and wanting to use the modern features of electronic parking meters does
not have to write off the remaining undepreciated monetary worth of their
conventional parking meters.
It is a common fact with conventional mechanical parking meters
that the clockwork and coin receiving and registering mechanism have a
useful life which is generally much longer than a duration of its period of
technological novelty. The electronic module of the present invention
takes advantage of the endurance of the mechanical components of
conventional parking meters to prolong the modernness of these
installations, and to extend a duration of their depreciable life. Therefore
the addition of an electronic module of the present invention to a
conventional parking meter adds to the net worth of a municipality's assets
and eliminates the capital write-off normally associated with a change-over
to a modern electronic meter.
In accordance to a second aspect of the present invention, the shell
of the electronic module has a first and second spaced apart faces enclosed
by a first and second sides and a top portion. The first and second sides
have each a light operable into an ON mode by the electronic circuitry at
substantially a same time as a transmission of the coded message. The
lights are operable into an OFF mode by a timer comprised in the electronic
circuitry, or by an reset receiver on the first face of the shell. When that
shell is mounted on a conventional parking meter and these lights are in an
ON mode, the conventional parking meter is visible from a great distance
as compared to other conventional parking meters.
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A law enforcement officer tending parking meters may thereby
readily identify from a distant location, a corner of a street for example,
all
parking meters on that street indicating a time expiry condition or a
condition of violation. This feature is particularly useful for reducing the
officer's usual inspection of all meters along a designated route in order to
identify those indicating an infringing condition.
In accordance to a third aspect of the present invention, the
electronic module comprises broadly a shell defining a hollow confor-
mation and having mounting means attachable to a conventional parking
meter. The electronic module also comprises an electronic circuitry
mounted inside the shell and having a power source for operating the
module. The electronic module of this third aspect of the present invention
fiuther has an electronic liquid crystal display screen mounted on a face of
the shell for displaying promotional messages to users of the conventional
parking meter.
The electronic display screen is connected to a programmable
memory capable of storing several characters of a complete message, and
to an input circuitry for controlling an operation thereof. The electronic
circuitry has a communication receiver for receiving a message to be
displayed on the liquid crystal display screen, and for storing this message
in the programmable memory.
An advantage of this third aspect of the present invention is that
promotional messages are optionally displayed to users of a conventional
parking meter having the electronic module mounted thereon. These
messages are preferably displayed continually during daylight time when
the power source is a solar panel for example.
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Alternatively, the electronic module of this third aspect of the
present invention may comprise a vehicle sensor affixed to the shell for
detecting from a distant point a vehicle parked in a parking space at
proximity on the conventional parking meter. In this latter case, a first
signal is received from the vehicle sensor and relayed to the input circuitry
for activating a first and a second timer controlling an operation of the
electronic display screen. The promotional messages are preferably
displayed on this optional third aspect of the present invention, from a time
soon after a vehicle parks near the parking meter and for a pre-determined
duration thereafter.
Hence, a municipality managing a conventional parking meter
having the electronic module according to this third aspect of the present
invention mounted thereon can generate income from a commercial
establishment located near the parking meter for example, by selling and
displaying advertisement messages pertaining to this establishment.
In accordance to yet a further aspect of the present invention, the
electronic module fits on top of a conventional parking meter having a
intermediate housing containing a coin receiving and registering
mechanism, a clockwork and an opened upper end having a number of
latch members about that opened upper end. The conventional parking
meter also normally has an upper housing having an opened plane and a set
of catch members near that opened plane. The set of catch members being
removably attachable to the number of latch members of the intermediate
housing such that the opened plane normally fits atop the opened upper
end, and that the upper housing covers the intermediate housing.
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In this latter aspect of the present invention, the electronic module
comprises a shell having an opening and a set of clasp members near that
opening. The set of clasp members being substantially similar in shape,
spacing and number as the set of catch members, whereby the shell is
optionally removably attachable to the intermediate housing in substitution
to the upper housing.
Furthermore, the opening of the shell has a substantially similar
outline as a contour and dimensions of the opened plane, whereby when the
shell is mounted on the opened upper end of the intermediate housing, the
shell is aesthetically and securely compatible with the intermediate housing
relative to a conventional mounting of the upper housing on the
intermediate housing.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiments of the invention will be further
understood from the following description, with reference to the drawings
in which:
- Figure 1 is a front and left side perspective view of a conventional
parking meter;
- Figure 2 is a front and left side perspective view of a conventional
parking meter with the electronic module of the present invention
mounted thereon;
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- Figure 3 is a cross section of a conventional parking meter and of
the electronic module of the present invention through line 3-3 of
Figure 2, wherein the electronic module of the present invention is
slightly raisedfrom an intermediate housing portion of the
conventional parking meter;
- Figure 4 is a front view of the electronic module of the present
invention;
- Figure 5 is a rear view of the electronic module of the present
invention;
- Figure 6 is a logic diagram explaining an operation of the vehicle
sensor of the electronic module of the first preferred embodiment;
- Figure 7 is a logic diagram explaining an operation of the liquid
crystal display and of the meter condition sensor of the electronic
module of the first preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figures 1 and 2, a conventional parking meter of the
prior art normally has an intermediate housing 10 containing a clockwork
and a coin receiving and registering mechanism. The conventional parking
meter generally also has a coin collection portion 12 which is attached to
a support post 14. The conventional parking meter of the prior art also
normally has an upper housing 16 having a transparent window 18 for
covering a time indicating dial, a time pointer pointing at this dial, a time
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expiry flag and a violative condition flag. The internal components of this
conventional parking meter are not all illustrated herein for not being part
of the present invention, and for being common to a person having ordinary
knowledge of parking meters.
The upper housing 16 is normally removably retained to the
intermediate housing 10 by catch and latch members which will be
explained in greater details when making reference particularly to Figures
3, 4 and 5.
The internal components of a conventional parking meter, as well
as the intermediate housing 10 and coin collection housing portion 12 are
normally made of cast iron, aluminium or stainless steel having a good
resistance to wear, corrosion and rough handling. Therefore at a time when
municipalities are considering the features of the modern electronic parking
meters, there still exists a multitude of conventional meters which have not
yet reached their useful life expectancy.
The electronic module 20 of the preferred embodiments is mounted
on the intermediate housing 10 of a conventional parking meter, in
substitution to the upper housing 16. The electronic module 20 has similar
mounting attachments as those of the upper housing 16, as will be
explained later, such that it is readily mountable on the intermediate
housing 10 without using any tools and without modifying the intermediate
housing 10.
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One of the key features of the electronic module 20 of the first
preferred embodiment is that it detects a raised position of one of the time
expiry flag 22 and of the violative condition flag of the conventional
parking meter. This detection is effected without touching the flag 22 such
that there is no physical connection between the electronic module 20 and
the clockwork or the coin receiving and registering mechanism of the
conventional meter.
The electronic module 20 of the preferred embodiments enhance the
operation of a conventional parking meter while using all of the mechanical
movements and lower housing portions of that meter such that the
remaining life of that conventional meter may be fully utilized.
The electronic module of the first preferred embodiment 20
comprises a shell 24 defining a hollow conformation, and having a
transparent window 26 being substantially the same size and shape as the
transparent window 18 of the upper housing 16 of the prior art. The shell
24 of the first preferred embodiment preferably has a first window 26 on
the front face thereof and a similar second window 26' on the rear face
thereof, such that a user of the parking meter having an electronic module
mounted thereon has a similar visual access to the time pointer and time
20 indicating dial of the meter as one would normally have with the upper
housing 16 of the prior art.
The shell 24 of the electronic module of the first preferred
embodiment further has a light 30 on a left side thereof and a similar light
32 on the right side thereof. These lights 30,32 are operable in an ON
mode by an electronic circuitry inside the shell 24 upon a time expiry
condition or a condition of violation of the parking meter. The lights 30,32
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are operable in an OFF mode by a timer comprised in the electronic
circuitry, or by a reset receiver 34 on a front face of the shell 24. The
operation of the lights 30,32 improves the visibility of the electronic
module whereby a law enforcement officer can identify a meter in an
expiry condition from across a street or from an intersection of two streets
for example.
In this first preferred embodiment, the reset receiver 34 is an
infrared-type receiver responsive to an infrared transmitter, which is
preferably enclosed in a portable electronic unit carried by the officer
issuing parking tickets.
The electronic module 20 of the first preferred embodiment also has
an electronic liquid crystal display 36 on the front face of the shell 24. The
electronic display may exhibit messages to instruct a user about metered
parking regulations, but it is preferably used to promote businesses located
near that meter.
The operation of the electronic liquid crystal display 36 preferably
starts once a vehicle arrives at a parking space in front of the meter, or
soon
thereafter when the driver of this vehicle wallcs towards the meter. The
display continues to scroll or pulse the message for a programmed period
of time, which is normally sufficient for displaying the entire message at
least once or twice. Once the programmed time value is reached, the
electronic circuitry of the module 20 shuts OFF the electronic liquid crystal
display 36 such that a power consumption of the electronic module is
maintained as low as possible.
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The liquid crystal display has an input circuitry for controlling an
operation thereof, and a programmable memory which is preferably
erasable and re-programmable in a wireless mode through an infrared
receiver. The infrared receiver is preferably the same receiver 34 as is used
to shut off the lights 30,32. The memory of the display 36 is preferably
programmed using a portable computer (not shown) having an infrared
transmitter being able to communicate with the infrared receiver 34 of the
display 36.
The electronic module 20 of the first preferred embodiment further
has on a top portion thereof, a solar panel 38 made of an array of solar
cells. The solar panel is connected to a battery charging means of the
electronic circuitry of the module 20, to recharge the battery of the
electronic module during daylight time.
Thereupon, the features of the electtonic module of a second
preferred embodiment may be limited to those of a liquid crystal display
screen as just described, whenever a municipality selects this single option.
In this case, the power source of the electronic circuitry may be limited to
the output of the solar panel 38, and the message is preferably displayed
continuously whenever an ambient light intensity is sufficient to generate
the required energy.
Referring now to Figures 3, 4 and 5, the electronic circuitry of the
module 20 of the first preferred embodiment is indicated by numeral 40,
and the battery supplying electrical power to the electronic circuitry is
indicated by numeral 42. The electronic circuitry 40 also has a meter
condition sensor 44 hanging downward therefrom and being positioned at
a distance from the time expiry flag 22 and from the violative condition
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flag 22' of the conventional parking meter. When the flags 22,22' are made
of ferrous metal, the meter condition sensor 44 is preferably a magnetic
type proximity sensor mounted at proximity of the flags 22, 22', such that
it is responsive to a raised position of one of these flags 22,22'. When the
flag 22,22' are made of a material not detectable in a magnetic field, the
meter condition sensor 44 is preferably a photoelectric-type sensor having
its light beam oriented to reflect on one of the flags 22,22' when this flag
is in an upper indicating position.
A preferred configuration of the meter condition sensor 44 of the
electronic module 20 of the first preferred embodiment is a pair of
photoelectric-type sensors connected in series to one-another, and spaced
apart a distance indicated by label'A'. This distance'A' is preferably wider
than a width of the time pointer (not shown) of the conventional parking
meter. The advantage of this configuration is that the time pointer
intersecting any one of the light beams of the meter condition sensor 44
does not cause the electronic circuitry 40 to read an infringing condition of
the meter. The flags 22 or 22' being much wider than the time pointer (not
shown) intersects both beams simultaneously causing a violative or time
expiry condition signal to be sent to the electronic circuitry 40.
A number of different types of mechanical and electro-mechanical
conventional parking meters have an electronic timer and a flashing light
to indicate a time expiry condition or a mechanical failure of the coin
receiving and registering mechanism. In that respect, it will become
apparent to the person having an ordinary skill in the art of electronics that
a similar photoelectric switch 44 responsive to light intensity, may be used
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to detect the operation of the flashing light on a conventional parking meter
of that type. Accordingly, the electronic module 20 of the present
invention is also usable with those electronic or electro-mechanic
conventional parking meters of recent times.
Referring now to Figure 5, the electronic module 20 of the first
preferred embodiment has a vehicle sensor 48 on a rear face thereof to
detect the presence of a vehicle in the metered parking space. This vehicle
sensor 48 is preferable an ultrasonic sensor similar to those commonly used
in modern electronic parking meters as described earlier.
The shell 24 preferably has thin spots 50,50' on its front and rear
faces respectively. These thin spots are easily drilled through such that the
infrared reset receiver 34 or the vehicle sensor 48 may optionally be
mounted on a right hand or a left hand portion of the front and rear faces
of the shell to accommodate a location of the meter relative to the metered
parking space for example.
Referring back to Figure 3 there is illustrated, a partial cross-section
of a conventional parking meter. The intermediate housing 10 generally
comprises a clockwork 60 and a coin receiving and registering mechanism
62 on the top of which there is the abnormal condition flags 22,22'. The
intermediate housing 10 further has a pair of front latch members 64, and
a rear latch member 66 which is movable in an up and down position. The
rear latch member 66 is lockable in a down position by a keyed lock 68.
The shell 24 of the electronic module of the preferred embodiments
has a pair of-front clasp members 70 which are substantially similar to
those of a pair of front catch members (not shown) of the upper housing 16
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of the prior art. There is also provided a rear clasp member 72 which is
substantially similar to a rear catch member (not shown) of the upper
housing 16 of the prior art. Furthermore, the shell 24 of the electronic
module 20 of the preferred embodiments has an opening on its lower end
which has an outline 74 similar in shape and dimensions as a contour of a
lower opened plane 76 of the upper housing 16 of the prior art, as better
seen on Figures l and 2.
The structural similarities thus described enable a mounting of the
electronic module 20 of the preferred embodiments in substitution to the
upper housing 16 of the prior art. The clasp members 70,72 engage with
the latch members 64,66 in a similar manner as a mounting of the upper
portion 16 on the intermediate housing 10. The structural similarities also
ensure that an opened upper end of the intermediate housing 10 is properly
sealed from dust and weather conditions, and that the electronic module 20
is aesthetically compatible with the lower portions 10,12 of the conven-
tional parking meter.
Referring now to the electronic circuitry 40 of the electronic module
of the first preferred embodiment, the actual circuit diagrams are not
provided herein for being common to persons knowledgeable in electronic
20 control devices. Accordingly, a person having a general knowledge of
electronic circuitry using the instructions given herein should be able to
construct the electronic circuitry 40 for the module 20 of the first preferred
embodiment. The electronic circuitry 40 comprises broadly the following
essential functions: receiving power from a battery; receiving a first signal
from the meter condition sensor 44; receiving a second signal from the
vehicle sensor 48; processing the first and second signal; and when
appropriate, transmitting a coded message to a remote receiver.
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The coded message is preferably transmitted when the violative
condition flag, or the expiry condition flag is in a raised position, and when
a vehicle is parked in the metered parking space. A second condition for
transmitting the coded message is when a parking space has been occupied
for a period longer than a prescribed maximum duration as allowed by
municipal bylaws.
The message to be transmitted to a remote receiver, to a centtal
computer at the municipality headquarters for example, comprises an
indication of the location of the meter, and an indication that the parking
meter is in an infringing condition. A parking meter attendant verifying
regularly with the central computer, is able to locate parking meters in a
condition of infringement, and to go directly to those meters to issue
parking tickets. The efficiency of the parking meter attendant is thereby
improved considerably.
The transmitter of the electronic module 20 is preferably a wireless
transmitter such that an installation of the electronic module 20 over a
conventional parking meter does not require any external wiring.
Similarly, the receiver 34 as previously described, may alternatively
be a radio-wave type receiver, or other types of modern receivers capable
of receiving a wireless communication. The programming of the memory
of the electtonic display screen 36 or a resetting of the lights 30,32 to an
OFF mode may thereby be effected from a remote central computer having
a wireless communication transmitter.
Referring now to Figures 6 and 7, the preferred method of operation
of the electronic module 20 of the first preferred embodiment is illustrated
therein and described as follows in steps form:
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a) The vehicle sensor 48 intermittently verifies the presence of a
vehicle in a parking space;
b) The vehicle sensor 48 acknowledges the presence of a vehicle and
closes a cycle relay activating a first and second timer;
c) The first timer activates the liquid crystal display 36 which exhibits
an advertisement message for the preset period of time of the second
timer;
d) Once the preset time of the second timer is expired, the meter
condition sensor 44 verifies that both flags 22,22' are in a lower
position;
e) If the meter condition sensor 44 detects one of the expiry time flag
22 and the violative condition flag 22' in a raised position, and the
vehicle sensor 48 continues to acknowledge a vehicle in the metered
parking space, a transmitter transmits a coded message to a remote
receiver, and the lights 30,32 are switched to an ON mode;
f) Once a message is transmitted, a latch relay is opened to open the
circuit energizing the display 36 and the coded message transmitter.
The latch relay closes the circuit again only when the vehicle leaves
the parking space, such that a coded message is only transmitted
once per parking violation.
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g) The lights 30,32 are switched OFF by the vehicle sensor 48 once the
vehicle in the metered parking space leaves the parking space or
else, the lights are turned OFF by the law enforcement officer
activating a hand held infrared transmitter communicating with the
infrared receiver 34.
h) If the vehicle sensor 48 does not detect the presence of a vehicle, the
cycle relay is opened and the latch relay is closed such that a next
vehicle will set a new cycle.
In the above preferred method of operation, the duration of the first
timer is sufficient for a driver of a vehicle to park his vehicle and to walk
towards the parking meter. The duration of the second sensor is sufficient
for allowing this driver to insert coins in the parking meter and to walls
away from the meter.
In the above preferred method of operation, both the vehicle sensor
and the meter condition sensor operate in an intermittent mode such that a
power consumption of the electronic module 20 is maintained at a low
level.
The electronic circuitry 40 of the first preferred embodiment may
advantageously comprise additional functions to further enhance the
operation of a conventional parking meter. In this respect, a dormant mode
may be incorporated in the circuitry to still lessen the consumption of
power by the module between vehicles, and during periods of free access
to parking spaces. Other practical features for the electronic module of the
present invention are numerous and include for examples, the accumulation
of statistics about a metered parking system such as tracking the usage time
and frequency of some parking spaces as compared to others.
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While the above description provides a full and complete disclosure
of the preferred embodiment of this invention, various modifications,
alternate constructions and equivalents may be employed without departing
from the true spirit and scope of the invention. Such changes might involve
alternate circuitry, components, structural arrangements, operable features
or the like. Therefore the above description and accompanying illustrations
should not be construed as limiting the scope of the invention which is
defined by the appended claims.
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