U.S. patent number 3,796,295 [Application Number 05/230,382] was granted by the patent office on 1974-03-12 for electronic metal coin analyser.
This patent grant is currently assigned to F.A.T.M.E. S.p.A.. Invention is credited to Sergio Montolivo, Giorgio Squartini.
United States Patent |
3,796,295 |
Montolivo , et al. |
March 12, 1974 |
ELECTRONIC METAL COIN ANALYSER
Abstract
The novel electronic metal coin analyzer is disclosed wherein a
coin to be analyzed falls through an inductance coil which is
coupled to the resonance circuit of an oscillator. As the coil
falls through the coil, a dynamic change in inductance is produced
in the coil and a resultant dynamic change of operating frequency
of the oscillator occurs. Specifically, for each coin, a band or
plurality of frequencies will be generated as the coin drops
through the coil. These frequency signals are further processed
through a plurality of band pass filters, one band pass filter for
each different type of coin, and serve to actuate a relay-operated
coin deflector only if the signals are originated by a coin for
whose acceptance the device is pre-set.
Inventors: |
Montolivo; Sergio (Rome,
IT), Squartini; Giorgio (Rome, IT) |
Assignee: |
F.A.T.M.E. S.p.A. (Rome,
IT)
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Family
ID: |
11244723 |
Appl.
No.: |
05/230,382 |
Filed: |
February 29, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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24316 |
Mar 31, 1970 |
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Foreign Application Priority Data
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Mar 31, 1969 [IT] |
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36093/69 |
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Current U.S.
Class: |
194/319;
194/346 |
Current CPC
Class: |
G07D
5/08 (20130101) |
Current International
Class: |
G07D
5/00 (20060101); G07f 003/02 () |
Field of
Search: |
;194/99,1R,1A
;209/81 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tollberg; Stanley H.
Assistant Examiner: Bartuska; Francis J.
Attorney, Agent or Firm: Browdy and Neimark
Parent Case Text
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of copending application
Ser. No. 24,316 filed Mar. 31, 1970 now abandoned.
Claims
1. An electronic coin analyzing device for screening types of coins
acceptable to a vending machine from coins not acceptable to a
vending machine, said device comprising:
a coin channel;
an inductance coil surrounding said coin channel;
controllable oscillator means coupled to said inductance coil for
normally generating a given output frequency, the output frequency
of said oscillator means being varied from said given frequency to
a plurality of other selectively different instantaneous
frequencies within a band in accordance with instantaneous
inductance variations in said coil caused by the falling of a coin
therethrough;
a deflector to cash in acceptable coins and to refund the
non-acceptable coins;
a plurality of filter means coupled in parallel to said oscillator,
each of said filter means having a pass band which corresponds to
the band of selectively different instantaneous oscillator
frequencies originated by a respective type of acceptable coin, the
pass bands of each filter being different to correspond to each
respective different type of acceptable coin; and
means coupled to each pass band filter and responsive to the output
thereof for processing signals transmitted therethrough and for
actuating said coin deflector, said means being responsive to the
time duration of each
2. A device as defined in claim 1, wherein a modulator coupled to a
fixed frequency oscillator is inserted between said oscillator
means and the pass band filter means, the output of said
controllable oscillator means comprising a modulating frequency for
modulating the output of said fixed frequency oscillator, said
modulated output of said fixed frequency
3. A device as defined in claim 1, wherein said means processing
signals transmitted through each pass band filter comprise, for
each filter, a detector unit interposed between said filter and
said deflector, each detector unit comprising a rectifying circuit,
an amplifying circuit, and
4. A device as defined in claim 3, wherein said means processing
said signals additionally comprise an OR signal connected to all
relays of the detector unit, a monostable circuit series connected
to said OR circuit, and a deflector actuating relay series
connected to said monostable
5. A device according to claim 3, wherein the output of each
detector unit is series connected to a coin counting device.
Description
This invention generally relates to the electronic circuitry arts,
and particularly concerns an electronic apparatus particularly
adapted for analyzing metal coins.
A plurality of circuits, machines, and apparatus exist in the art
for analyzing and counting metal coins. Such devices have their
main field of utility in automatic vending machines, and in
machines operative for the specific analysis and counting of coins.
The typical prior art mechanisms serve to discern the type and
validity of the coin by means of various selectors of the
mechanical or electromechanical type on the basis of geometric
characteristics of the coins such as the coin diameter. coin
thickness, nature of the rim, whether smooth or knurled, the
presence or absence of central bores, or on the basis of other
physical characteristics of the coin such as weight. Such devices,
however, are generally not suitable to discard counterfeit coins
when, for example, the geometric characteristics of the counterfeit
coin are sufficiently close to those of a genuine coin. This
disadvantage of prior art mechanisms is particularly noted when the
coins accepted by the machine are thereafter utilized for returning
change to the user. Furthermore, such devices are subject to wear
and therefore require frequent maintenance work.
Also in existence in the prior art are machines which utilize
electronic selectors, rather than selectors of the mechanical or
electromechanical type as above-discussed. With such electronic
mechanisms, the analysis of the coins is performed on the basis of
determining one or more electrical characteristics of the material
from which the coins are made, such as the magnetic permeability of
the coin, or its electrical conductivity. Yet, the typical
electronic device currently available in the art has the
inconvenience of requiring an individual channel for each type of
coin which the machine must be able to accept. Typical of this type
of prior art electronic selector is that depicted in the Turillon
U.S. Pat. No. 3,317,016 wherein a coin is dropped into the center
of an inductance coil so as to vary the inductance thereof by a
predetermined amount, this inductance variation producing a
specified shift in the frequency generated by an oscillator coupled
to the inductance coil.
SUMMARY OF THE INVENTION
As should be apparent, a need exists in this art for an apparatus
which can recognize and select different types of coins, as well as
separate good coins from counterfeit coins, on the basis of
measurements of electrical and magnetic parameters which are
characteristic of the coins, and which apparatus does not suffer
from the disadvantages of the prior art as above-discussed. It is
the primary objective of the instant invention to provide such a
machine which fills this need.
A further, more specific, yet equally important objective of the
instant invention concerns the provision of an electronic device
for the recognition or discernment of various types of coins while
they drop in a free fall, without stopping within a single passage.
As can be appreciated, such an electronic device would have great
utility in automatic vending machines and in machines for the
specific analysis and counting of coins.
These objects, as well as others which will become apparent as the
description proceeds, are implemented by the instant invention in
which the reading device essentially comprises a channel of plastic
material around which a coil of copper wire is wound. The coins to
be discerned are introduced into the device and fall freely through
the channel under the influence of gravity. As such coins fall
through the zone of the channel around which the coil is wound, a
variation of the electromagnetic characteristics of the medium
surrounded by the coil is therefore obviously produced and,
thereby, a variation of inductance in the coil is evident.
This inductance variation of the coil takes place in what is termed
a "dynamic" fashion in that, as the coin freely falls, a plurality
of instantaneous different inductance changes takes place.
Specifically, and in the event that the coin dropped has
ferromagnetic characteristics, an increase in instantaneous
inductance of the coil is noted beginning from the initial
inductance of the coil and gradually increasing so as to reach a
maximum change of inductance at the instant wherein the coin is in
the center of the coil. As the coin continues to fall, the
inductance change of the coil decreases in like manner. Similarly,
and for non-ferromagnetic coins, there prevails instead an effect
of electrical conductivity and, in this event, a negative variation
of inductance is produced due to losses caused by the Joule effect
and the film effect. Importantly, however, the inductance
variations of the coin for both the ferromagnetic or
non-ferromagnetic coin is dynamic in that it continuously changes
as the coin drops therethrough. Further, it should be appreciated
that for both basic types of coins, for any given type of coin
material, the variations in the absolute magnitude of coil
inductance obtained is further a function of the geometric
dimensions of the coins themselves.
The instant invention, therefore, is characterized by the fact that
it comprises but a single channel for the introduction of coins of
the various types and the utilization therewith of but a single
reading device which is capable of identifying a given coin which
is freely falling therethrough on the basis of inductance
variations, as to the absolute value and design, of the reading
coil.
In the preferred embodiment of the instant invention, the selector
is characterized by the fact that the reading coil forms part of a
resonant circuit of an oscillator having a "rest" frequency on the
order of magnitude of 70 kHz. In this fashion, an instantaneous
variation of the output frequency of the oscillator will occur due
to each instantaneous change in inductance of the reading coil.
Thus, for the instantaneous inductance variation of the coil
associated with each point of the reading channel as the coin
passes therethrough, there corresponds an instantaneous frequency
variation of the oscillator. Thus, as a single coin drops through
the coin channel and thus through the reading coil, a plurality of
different frequencies will be generated by the oscillator, this
plurality of frequency variations lying within a specific band of
frequencies as predetermined for each different type or
denomination of coin, and it is this band of frequencies generated
for each coin which constitutes the signal for subsequently
actuating the analyzing circuitry of the invention. This generation
of a plurality of different frequencies by each coin passing
through the coil in a free fall is an important aspect of the
instant invention, as will be appreciated from the detailed
description thereof hereinbelow.
So that the apparatus of the instant invention can be operated to
discern and analyze a plurality of different coin types, such as
different denominations of coins, the preferred embodiment of the
instant invention comprises an analyzer or selector which is
furthermore characterized by the act that the output of the
oscillating circuit is applied to a certain number N of parallel
circuits, equal to the number N of the coins of different types or
denominations which the device is intended to discern. Each of
these subsequent circuits are essentially formed by a band pass
filter and by a suitable detector device. Each band pass filter has
a pass band which corresponds to the band of frequencies caused to
be generated by a different type of denomination of coin.
Thus, the output of the final signal detector device of the overall
circuit serves to provide a signal identifying the type of coin,
i.e., a signal which is present when and only when a coin
associated to the specific circuit is falling through the coil.
Accordingly, if a coin of a particular type or denomination
associated with circuit number 2 is introduced into the coin slot
and falls through the coil, the instantaneous frequencies of the
oscillator will shift and be such that the plurality of frequencies
generated by the oscillator due to the passage of this single coin
merely involves or comprises the frequency band of the filter
relating to circuit number 2. Consequently, there will be present
an identifying signal at the output of the circuit, while none will
be present at the output of the other parallel circuits.
For proper operation of the device, no identification signal must
be present in the output of the individual circuits during the
passage of a coin which does not belong to the group of N coins for
which the selector has been pre-set. This correct operation is
obtained merely through a suitable selection of the band width of
the individual filters, this band width being correlated with the
band of frequencies generated by the falling of each acceptable
type of coin, as well as a suitable selection of the reciprocal
positions or difference of these bands along the frequency
scale.
The identification signals issuing from each single channel contain
the necessary information for operation of the coin selection
device, and for the operation of the device which accepts the coins
which are considered genuine and which refuses those coins which
are considered counterfeit.
These signals passing through the individual band pass filters
control a suitable processing and counting network and
simultaneously are fed into the input of an OR circuit. If a coin
which is considered genuine is introduced into the selector, a
signal having the logical value 1 will be present as the output of
one of the N parallel circuits, and therefore at the output of the
OR circuit, a signal having the logical value 1 will be present. In
case the coins are considered counterfeit, all of the N inputs of
the OR circuit would have the logical value 0, i.e., an absence of
a signal and likewise, the output of the 0 signal will have the
logical value 0.
Therefore, the output from the OR circuit is adapted to control an
exchange device for cashing the coins which are considered genuine
and for refusing those coins which are considered counterfeit. In
this respect, it should further be appreciated that the duration of
the signal which presents itself at the output of the filter
belonging to the general circuit is proportional to the time
interval during which the instantaneous frequencies generated by
the oscillator due to a single falling coin lies within the pass
band of the filter. The subsequent detector circuit is designed to
provide an output signal of well defined amplitude and duration
only when the time interval of the input signal thereto exceeds a
suitable limit value. By this time discrimination, the discernment
of coins, such as counterfeit coins, is permitted even if the coins
produce frequency variations of the same type, i.e. same size and
similar absolute value, as a genuine coin since such frequency
variations undoubtedly would not occur with a counterfeit coin for
the same time interval as would be the case if the coin were
genuine. This feature essentially provides discrimination as to
coin size.
As concerns this time discrimination function, it should further be
appreciated that the output of an individual filter will have a
signal which is sufficiently long to be considered valid by the
following detecting device only when the instantaneous frequency
generated by the oscillator falls within and near the center of the
pass band of one of the pass band filters at the moment wherein the
falling coin is in the center of the reading coil. This manner of
operation is assured through suitable selection of the time
interval detection circuitry in association with the width and
absolute value of the pass band filters as will appear
hereinbelow.
The analyzer forming the subject matter of the instant inventon can
readily be pre-set for any type of coin since it is merely
necessary to adapt a filter having a suitable pass band relating to
the type of coin to enable the selector to recognize and count the
coin.
Furthermore, the instant invention is capable of assessing the
coins without need for stopping the travel of the coins in the
reading coil. In other words, the coins are neither touched nor
hindered during their free fall through the coil and the selector
is sufficiently quick in its response to ascertain the passage of
two or more coins introduced in succession and even in contact with
each other in said selector.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood and further features and
advantages thereof will become apparent from the following detailed
description of the preferred inventive embodiment, such description
making reference to the attached drawings wherein:
FIG. 1 is a sectional view according to line I--I of FIG. 2
schematically representing the selector layout,
FIG. 2 is a cross-sectional view according to line II--II of FIG.
1,
FIG. 3 is a vertical sectional view according to line III--III of
FIG. 1, and
FIG. 4 is a complete block diagram of the selector.
DETAILED DESCRIPTION OF THE PREFERRED INVENTIVE EMBODIMENT
Reference is now made to FIGS. 1-3 and particularly to FIG. 1
wherein it should be noted that the coins are introduced through a
calibrated slot 10 or through other known pre-selection means which
prevent the introduction of coins which are bent, twisted, or
having sizes exceeding those of the maximum coin size admitted,
which could remain blocked within the device. The coins pass first
through an entrance passage 12 having a rectangular cross-section,
which can also be made from metallic material. Through the passage
12 the coins are fed to the reading device, generally indicated at
14, which comprises a conduit 16, made of electrically insulating
and non-magnetic material, having also a rectangular cross-section.
The conduit 16 is provided with a housing 18 for a reading coil 20,
which is connected by means of a flexible wire (not shown) to the
resonant circuit of an oscillator whose frequency it determines.
Beneath the reading device 14 there extends a third conduit 22,
which can also be made from metallic material. Conduit 22 has a
housing 24 for a deflector 26, controlled by an electromechanical
relay 28. In the location of the deflector the conduit 22 branches
into two channels of a similarly rectangular section, which are
directed into two different directions: the first, indicated at 30
in FIG. 1, conveys the good coins towards a cash box, while the
second, indicated at 32, forms an inclined branch which directs the
rejected coins towards the coin returning door of the vending
machine.
FIG. 3 shows how in the preferred embodiment the deflector 26, in
its rest or inoperative position, is positioned so as to convey the
coins introduced through the slot 10 towards the coin restoring
channel 32. This ensures that, in the case of failure of the device
or in the absence of a feed voltage, any coin, whether good or
counterfeit, is directly restored without the need of any
additional moves.
Only when the device operates correctly and the introduced coin has
been recognized as good and computed by the reading device 14, at
the end of relay 28 a control pulse is present which, by actuating
the deflector 26 causes the coin to be switched into the channel
30.
The block diagram of FIG. 4 shows a preferred form of circuit for
the selector. The reading coil 20 is connected to the resonant
circuit which determines the oscillating frequency of the
oscillator 34, whose output is connected either directly, or, as it
will be illustrated, through a block 52, in parallel to the input
of a plurality of pass band filters F.sub.i (i being = 1, 2 . . .
N) N being the number of coin denominations which the device must
be capable of checking.
The output of each filter is connected to a detector device
DR.sub.i, essentially consisting, as far as the electrical
functions are concerned, of an amplifyer 36 for the filter signals,
of a rectifying circuit 38 for the amplified signals, and of a
relay 40. The detector device further functions as a time
discriminator in that no output will be produced unless the time
duration of the input was sufficiently long. This may be
structurally achieved in various known manners, such as by the
provision of a capacitor charging element and a discharge or
breakdown device coupled to the rectifier output. The outputs of
the various detecting devices control, through the connections 42,
the successive counting circuit for the good coins and furthermore
control in parallel a logical OR circuit, indicated at 44 in FIG.
4, whose output supplied a pulse when a pulse is present on one of
the inputs. This latter pulse control through a monostable circuit
46, the relay 28 which actuates the deflector 26.
When a good coin 48, after having been introduced through slot 10,
passes through the zone of the reading coil 20, this coin will
produce a plurality of instantaneous variations in the inductance
of the coil as above-described, so as to cause the oscillator 34 to
generate a plurality of instantaneous frequencies. This plurality
of instantaneous frequencies generated would correspond with the
pass band of filter F.sub.i which is provided for the particular
type of coin introduced. Accordingly, this signal will pass through
the filter and the filter will have an output therefrom which has a
time duration which is sufficiently long to actuate the detecting
device whose output will supply a signal having a logical level 1.
At this point, it should be understood that the instantaneous
frequencies generated by the oscillator due to the passage of a
coin will have a band width on the order of tens of thousands of Hz
in the preferred inventive embodiment simply through selection of
coil and oscillator parameters. Due to this wide band of
frequencies generated for each coin, discrimination between the
various types of coins can be made in a considerably more facile
manner. This is another advantage of the "dynamic" frequency
generation aspect of the instant invention.
Coninuing, if the output from the detecting device has the logical
level 1, this signal will actuate the coin counting device by means
of connections 42. The same signal will also actuate relay 28 so as
to switch the deflector 26 about its pivot 50 so as to close the
entrance to the coin restoring channel 32, and so as to open the
entrance of the channel 30 for a time which is sufficiently long to
ensure the passage of the computed coin. Immediately thereafter,
the relay 28 will revert to its inoperative position and the
deflector 26 will again close the access to channel 30.
In order to simplify the design of the pass band filters and so as
to bring them to operate in a lower field of frequencies, between
the output of the oscillator 34 and the input of the pass band
filters a block 52 can be inserted, comprising a modulator which is
piloted by a fixed frequency oscillator. Thereby, at the output of
block 52 a signal can be obtained, whose frequency is smaller than
the input frequency, and is equal to the difference between the
frequency of the fixed oscillator and the frequency of the variable
oscillator. Since the absolute frequency deviations of the variable
oscillator are integrally rendered as absolute frequency deviations
at the output of the modulator, while, on the other hand, the
percent frequency deviations at the output of the modulator are
increased, it is clear that also the ease of filtration increases,
since it is based upon the percent frequency deviations and not on
the absolute frequency deviations.
It is also possible to apply a plurality of the device just
described to the same machine to control the same deflector, so
that the coins dropped into the slot 10 will pass in succession
through them. In this manner the selection can occur through a
number of independent reading devices, to each being entrusted the
task of identifying only one part of the group of N coins of
different denominations which the selector must recognize and
discern. For this purpose it is sufficient to connect each reading
coil to an own oscillator followed by the assembly of filters and
detecting circuits. By establishing the frequency of the various
oscillators in a suitable manner, such an arrangement permits to
adopt, for each group of coins assigned to a given reading device,
that frequency at which the maximum percent frequency variations
are obtained for those types of coins, so as to simplify the
problems relating to the filtration.
In summary, then, it should be appreciated that the instant
invention as described operates in an entirely different manner
than the operation associated with the prior art, in that a true
"dynamic" operation is effected. When a coin passes by the sensing
inductance coil 20, a plurality of different variations of
inductance of the coil takes place which causes the controllable
oscillator means 34, which oscillator normally generates a given or
rest output frequency, to vary its operating or output frequency
from the given frequency to a plurality of selectively different
frequencies, i.e., an entire band of frequencies for each coin.
This band of frequencies is characterized and corresponds to a coin
of one denomination or type. If a differeent type of coin passes by
the inductance coil 20, the output from the oscillator 34 would
exhibit a different band of frequency components. A plurality of
detecting circuits coupled in parallel comprising band pass filters
are connected to the output of the oscillator and each of these
filters have a different pass band which corresponds to the bands
of selectively different oscillator frequencies originated by each
respective different type of "acceptable" coin. If any one of the
filters exhibits an output then this indicates that proper
instantaneous frequencies were generated by the oscillator. If the
output occurs over a sufficient time duration, this fact, in
addition to the proper frequency characteristics, is indicative of
the presence of an "acceptable" coin and the coin deflection means
is likewise actuated.
It is obvious that many and different variants and changes may be
applied by the experts in the art to the above-illustrated
preferred form of embodiment of the present invention, without
departing from its spirit and scope, it being understood that all
these variants and changes are encompassed within the scope of the
invention.
* * * * *