1. Field of the Invention:
[0001] The present invention relates to bill acceptor technology and more particularly,
to an in-passage sensing type coin dispenser system, which uses electrodes at each
coin tube to induce coupling capacitance and a detection circuit to measure the value
of each induced coupling capacitance indicative of the coin storage status in each
coin tube.
2. Description of the Related Art:
[0002] Following fast development of modern technology, convenience and rapidness are highly
demanded in our modern daily life. Nowadays, different automatic vending machines,
card dispensers, ticket machines and bill exchange machines are used everywhere to
sell different products without serviceman. These machines are highly appreciated
for the advantage of saving much labor and bringing convenience to people. With the
selling of more and more kinds of goods, advanced vending machines need added functions.
[0003] Further, commercial automatic vending machines and amusement machines commonly provide
a coin acceptor for allowing people to insert coins, achieving unmanned operation
and self-checkout. Further, a coin-operated automatic vending machine or amusement
machine generally uses a coin validator module to validate the authenticity and value
of each inserted coin or token. Different coins or tokens have different sizes. After
validation of an inserted coin, the coin will be dispensed into one of a number of
coin tubes inside the machine. If the number of coins stored in one coin tube reaches
a predetermined high level, the coin dispenser cannot dispense any further coin into
the respective coin tube. If the coin storage status of one coin tube reaches a predetermined
low level, the coin hopper of the machine cannot discharge coins from the respective
coin tube, ensuring normal operation of the machine.
[0004] At the present time, non-contact type displacement sensors are commonly used in coin-operated
vending machines and amusement machines to detect the storage status of coins in each
coin tube. These non-contact type displacement sensors include ultrasonic displacement
sensors, magnetic displacement sensors and optical displacement sensors. An ultrasonic
displacement sensor transmits an ultrasonic wave onto a coin and to receive reflection
of ultrasonic wave from the coin. The energy difference between the transmitted ultrasonic
wave and reflected ultrasonic wave, i.e., the attenuation of the ultrasonic energy
indicative of the position of the coin is measured by a controller. An ultrasonic
displacement sensor has the disadvantages of large size and high cost. Further, the
signal strength of an ultrasonic displacement sensor is indirectly proportional to
the distance of the coin. For use with an ultrasonic displacement sensor, the length
of the coin tubes must be limited. A coin tube having an excessive length may contribute
to the problems of scattering attenuation, insufficiency of excited energy and recognition
error. A magnetic displacement sensor is adapted to induce an eddy current upon presence
of a coin within the effective sensing range. The value of the induced eddy current
is measured by a controller to figure out the current position of the coin. A magnetic
displacement sensor is simply suitable for a short distance sensing application. When
used in a coin tube, the exciting frequency of the sensing coil will be increased,
complicating posterior signal processing and relatively increasing the cost.
[0005] Further, an optical displacement sensor is adapted to detect the position of coins
in a coin tube by means of light chopping. A light reflector is provided to reflect
emitted light onto the coin tube. When a coin passes to chop the light beam, a shadow
is produced. A controller calculates the position of the coin subject to change of
the shadow. An optical displacement sensor is free from the interference of electronic
noises, and has the advantage of low signal attenuation. The size of the coin tube
does not significantly affect the sensing accuracy of the optical displacement sensor.
When increasing the size of the coin tube, the size of the light reflector must be
relatively increased. However, because the light reflector is inexpensive, increasing
the size of the light reflector does not increase much the cost of the optical displacement
sensor. However, recognition error may occur if the optical displacement sensor is
used under a dust or polluted environment.
[0006] In view of the above statement, there is still room for improvement in coin detection
SUMMARY OF THE INVENTION
[0007] The present invention has been accomplished under the circumstances in view. It is
therefore one object of the present invention to provide an in-passage sensing type
coin dispenser system, which detects the coin storage status in each coin tube of
the coin dispenser system by means of capacitive coupling technology, having the advantages
of simple structure, rapid response, workability under high temperature, dust and/or
polluted environment, ease of installation and low cost.
[0008] To achieve this and other objects of the present invention, an in-passage sensing
type coin dispenser system comprises a housing, a coin tubes mounted in the housing
for storing predetermined metal coins having a predetermined value and size, a coin
dispensing unit mounted in the housing at a top side for validating the authenticity
and value of metal coins and dispensing validated metal coins into the coin tubes,
a coin hopper mounted in the housing at a bottom side for discharging metal coins
out of the coin tubes, and a sensor module, which comprises an upper set of electrodes
mounted at the outer perimeter of each coin tube near the top end thereof for sensing
the presence of metal coins in the respective coin tube and generating a corresponding
first induced current of analog signal, a lower set of electrodes mounted at the outer
perimeter of each coin tube near the bottom end thereof for sensing the presence of
said metal coins in the respective coin tube and generating a corresponding second
induced current of analog signal, and a detection circuit electrically coupled with
the upper and lower sets of electrodes and adapted to receive the first induced current
of analog signal and second induced current of analog signal. If the detection circuit
receives a first induced current of analog signal from the upper set of electrodes
at one coin tube, the detection circuit immediately stops the coin dispenser unit
from dispensing metal coins into the respective coin tube. If the detection circuit
receives a second induced current of analog signal from the lower set of electrodes
at one coin tube, the detection circuit immediately stops the coin hopper from discharging
metal coins out of the respective coin tube.
[0009] In an alternate form of the present invention, the in-passage sensing type coin dispenser
system comprises a housing, a coin tubes mounted in the housing for storing predetermined
metal coins having a predetermined value and size, a coin dispensing unit mounted
in the housing at a top side for validating the authenticity and value of metal coins
and dispensing validated metal coins into the coin tubes, a coin hopper mounted in
the housing at a bottom side for discharging metal coins out of the coin tubes, and
a sensor module, which comprises multiple sets of electrodes bilaterally and longitudinally
mounted at the outer perimeter of each coin tube along the length thereof for generating
a coupling capacitance, and a detection circuit electrically coupled with the multiple
sets of electrodes and adapted to receive the coupling capacitance and to convert
the coupling capacitance received from the set of electrodes at each coin tube into
a corresponding digital signal indicative of the number of metal coins being stored
in the respective coin tube.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010]
FIG. 1 is an elevational view of an in-passage sensing type coin dispenser system
in accordance with the present invention.
FIG. 2 is an exploded view of the in-passage sensing type coin dispenser system in
accordance with the present invention.
FIG. 3 is a block diagram of the sensor module of the in-passage sensing type coin
dispenser system in accordance with the present invention.
FIG. 4 is a schematic sectional view illustrating electrodes mounted at the outer
perimeters of coin tubes near top and bottom ends thereof in accordance with the present
invention.
FIG. 5 is similar to FIG. 4, illustrating the storage of metal coins in one coin tube
at a low-level status and the storage of metal coins in the other coin tube at a full-level
status.
FIG. 6 is a schematic sectional view illustrating electrodes mounted at the outer
perimeters of coin tubes in a parallel manner and extended along the length of the
coin tubes in accordance with the present invention.
FIG. 7 corresponds to FIG. 6, illustrating the storage amount of metal coins in one
coin tube changed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] Referring to FIGS. 1-5, an in-passage sensing type coin dispenser system in accordance
with the present invention is shown. The coin dispenser system comprises a machine
main unit
1, and a set of coin tubes
2.
[0012] The machine main unit
1 comprises a housing
11 defining therein an accommodation space
10, a coin dispensing unit
12 mounted in a top side in the accommodation space
10 inside the housing
11, a sensor module
13 mounted in a bottom side of the coin dispensing unit
12, and a coin hopper
14 mounted in a bottom side in the accommodation space
10 inside the housing
11. The set of coin tubes
2 is mounted in the coin hopper
14 at the bottom side of the coin dispensing unit
12. The coin dispensing unit
12 comprises a coin inlet
120 disposed at a top side thereof for receiving metal coins
3, a coin validator module
121 for validating the authenticity and values of metal coins
3 being put into the coin inlet
120, and a coin dispensing module
122 for dispensing validated metal coins
3 into the coin tubes
2 in a proper order.
[0013] The sensor module
13 comprises multiple sets of electrodes
131 respectively mounted on the outer perimeters of the coin tubes
2 at different elevations, a detection circuit
132 electrically coupled with the multiple sets of electrodes
131 by electric wires and arranged at the bottom side of the coin dispenser unit
12. In actual application, the detection circuit
132 can be mounted inside the coin dispenser unit
12, or at any suitable location inside the housing
11 to detect change of capacitance of storage metal coins
3 in each of the coin tubes
2. Further, the coin hopper
14 is mounted at the bottom side in the accommodation space
10 inside the housing
11 to accommodate the coin tubes
2 and to propel storage metal coins
3 out of the coin tubes
2 for coin exchange or giving change.
[0014] The coin tubes
2 are cylindrical coin storage devices for receiving sorted metal coins
3, each defining a cylindrical passage
20 that has a specific inner diameter for accommodating a predetermined number of metal
coins
3 having a specific value.
[0015] As stated above, the coin dispenser unit
12 is mounted in the housing
11 of the machine main unit
1 at the top side; the hopper
14 is mounted in the housing
11 at the bottom side of the coin tubes
2; the multiple sets of electrodes
131 of the sensor module
13 are respectively mounted around the outer perimeters of the coin tubes
2 near the opposing top and bottom ends thereof and respectively electrically connected
to the positive and negative terminals of the detection circuit
132; each coin tube
2 defines therein a cylindrical passage
20 having a specific inner diameter for accommodating a predetermined number of metal
coins
3. Further, the electrodes
131 of the sensor module
13 can be configured having a thickness equal to, or, greater or smaller than the thickness
of the metal coins
3 to be dispensed into the coin tubes
2.
[0016] When metal coins
3 are guided into the coin tubes
2 by the coin dispenser unit
12, the metal coins
3 are kept in the cylindrical passages
20 of the respective coin tubes
2 between the respective upper and lower sets of electrodes
131. At this time, a change of capacitance occurs in the capacitive coupling between the
electrodes
131 and the storage metal coins
3 in each coin tube
2, causing the upper or lower set of electrodes
131 at each coin tube
2 to provide a respective induced current of analog signal to the detection circuit
132 for conversion into a respective digital signal indicative of the capacitance value
between the upper or lower set of electrodes
131 at the respective coin tube
2. If the detection circuit
132 detects a change in the capacitance value between the lower set of electrode
131 at one coin tube
2, it means that the respective coin tube
2 has metal coin(s)
3 stored therein. At this time, this coin tube
2 is at a low-level status, and the coin hopper
14 is prohibited from discharging metal coins. If the detection circuit
132 detects a change in the capacitance value between the upper set of electrode
131 at one coin tube
2, it means that the respective coin tube
2 has metal coin(s)
3 stored therein. At this time, this coin tube
2 is at a full-level status, and the coin dispenser unit
12 is stopped from dispensing metal coins into the coin tubes
2. Subject to the arrangement described above, the invention effectively detects the
coin storage status of each coin tube
2 to be at a low level or full level status. Further, the electrodes
131 have the advantages of simple structure, rapid response, workability under high temperature,
dust and/or polluted environment, ease of installation and low cost.
[0017] Referring to FIGS. 6 and 7, in an alternate form of the present invention, two electrodes
131 are bilaterally and longitudinally mounted at the outer perimeter of each coin tube
2 along the length of the respective coin tube
2, and electrically connected to the detection circuit
132. During operation, a capacitance is induced between the two electrodes
131 indicative of the amount of metal coins
3 stored in the cylindrical passage
20. Further, the surface area of the electrodes
131 can be increased to relatively increase the sensitivity, assuring a high level of
sensing reliability.
[0018] When metal coins
3 are put into the cylindrical passage
20 in each coin tube
2, the capacitance between the two electrodes
131 at the outer perimeter of the respective coin tube
2 is changed, generating an induced current that is measured by the detection circuit
132 and converted into a corresponding digital signal indicative of the amount of metal
coins
3 in the cylindrical passage
20 of the respective coin tube
2.
[0019] Referring to FIGS. 2, 3, 5 and 7 again, the invention is characterized by arranging
the electrodes
131 of the sensor module
13 at the outer perimeter of each coin tube
2 in the coin hopper
14 at the bottom side of the coin dispenser unit
12 inside the housing
11 of the machine main unit
1 and electrically connecting the electrodes
131 to the detection circuit
132 such that when metal coins
3 are dispensed into the cylindrical passage
20 in each coin tube
2, a change of capacitance between the electrodes
131 at the respective coin tube
2 occurs, and the detection circuit
132 measures the capacitance value and converts it into a digital signal indicative of
the low-level or high-level coin storage status of the respective coin tube
2 or the amount of metal coins
3 being stored in the respective coin tube
2. This coin sensing method is simple, highly reliable, and cost effective.
[0020] Although a particular embodiment of the invention has been described in detail for
purposes of illustration, various modifications and enhancements may be made without
departing from the spirit and scope of the invention. Accordingly, the invention is
not to be limited except as by the appended claims.
1. An in-passage sensing type coin dispenser system, comprising:
a machine main unit comprising a housing;
a coin tubes mounted in said housing, each said coin tube defining therein a cylindrical
passage for storing predetermined metal coins having a predetermined value and size;
a coin dispensing unit mounted in a top side in said housing, said coin dispensing
unit comprising a coin inlet disposed at a top side thereof for receiving said metal
coins, a coin validator module for validating the authenticity and values of the metal
coins being put into said coin inlet, and a coin dispensing module for dispensing
validated said metal coins into said coin tubes;
a coin hopper mounted in said housing for discharging said metal coins out of said
coin tubes; and
a sensor module comprising an upper set of electrodes mounted at the outer perimeter
of each said coin tube near a top end thereof for sensing the presence of said metal
coins in the respective said coin tube and generating a corresponding first induced
current of analog signal, a lower set of electrodes mounted at the outer perimeter
of each said coin tube near a bottom end thereof for sensing the presence of said
metal coins in the respective said coin tube and generating a corresponding second
induced current of analog signal, and a detection circuit electrically coupled with
each said upper set of electrodes and each said lower set of electrodes adapted to
receive said first induced current of analog signal and said second induced current
of analog signal, detection circuit stopping said coin dispenser unit from dispensing
said metal coins into each said coin tube when received said first induced current
of analog signal from the associating upper set of electrodes, said detection circuit
stopping said coin hopper from discharging said metal coins out of each said coin
tube when received said second induced current of analog signal from the associating
lower set of electrodes.
2. The in-passage sensing type coin dispenser system as claimed in claim 1, wherein said
detection circuit converts said first induced current of analog signal into a first
digital signal indicative of a full-level metal coin storage status of the respective
said coin tube and said second induced current of analog signal into a second digital
signal indicative of a low-level metal coin storage status of the respective said
coin tube.
3. The in-passage sensing type in dispenser system as claimed in claim 1, wherein each
said electrode of said sensor module is configured having a thickness equal to the
thickness of one individual said metal coin.
4. The in-passage sensing type in dispenser system as claimed in claim 1, wherein each
said electrode of said sensor module is configured having a thickness greater than
the thickness of one individual said metal coin.
5. The in-passage sensing type in dispenser system as claimed in claim 1, wherein each
said electrode of said sensor module is configured having a thickness smaller than
the thickness of one individual said metal coin.
6. An in-passage sensing type coin dispenser system, comprising:
a machine main unit comprising a housing;
a coin tubes mounted in said housing, each said coin tube defining therein a cylindrical
passage for storing predetermined metal coins having a predetermined size and value;
a coin dispensing unit mounted in a top side in said housing, said coin dispensing
unit comprising a coin inlet disposed at a top side thereof for receiving said metal
coins, a coin validator module for validating the authenticity and values of metal
coins being put into said coin inlet, and a coin dispensing module for dispensing
validated said metal coins into said coin tubes;
a coin hopper mounted in said housing for discharging said metal coins out of said
coin tubes; and
a sensor module comprising multiple sets of electrodes respectively and bilaterally
mounted at the outer perimeter of each
said coin tube and longitudinally extending along the length of each said coin tube
for generating a coupling capacitance, and a detection circuit electrically coupled
with said multiple sets of electrodes and adapted to receive said coupling capacitance
and to measure the value of said coupling capacitance that is indicative of the number
of said metal coins being stored in the respective said coin tube.
7. The in-passage sensing type in dispenser system as claimed in claim 6, wherein said
detection circuit converts the coupling capacitance received from the set of electrodes
at each said coin tube into a corresponding digital signal indicative of the number
of said metal coins being stored in the respective said coin tube.
8. The in-passage sensing type in dispenser system as claimed in claim 6, wherein each
set of electrodes at each said coin tube has a vertical height extending along the
length of the respective said coin tube over the combined thickness of a stack of
a predetermined number of said metal coins.