GB2212313A - Identifying articles - Google Patents

Abstract

Method of and apparatus for identifying an article with a known characteristic, such as, the denomination of a milled coin, capable of interfering with a path of radiation, such as, visible light or infra-red radiation, wherein an article (200) to be identified is presented to an emitted radiation path, any resulting interference of the path is detected and then it is determined whether such interference is representative of the known characteristic and, if so, the identity of the article. The invention is particularly applicable to coin sorting apparatus. <IMAGE>

Description

ARTICLE IDENTIFICATION DESCRIPTION This invention relates generally to article identification, particularly, but not exclusively, to a method of and apparatus for identifying an article, preferably a generally planar article, for instance, a disc-shaped article, such as, a coin, with a known characteristic, for instance, a dimension or surface structure, thereof. Such inventive method and apparatus is particularly useful in the field of coin sorting.

In accordance with one aspect of the invention, there is provided a method of identifying an article with a known characteristic capable of interfering with a path of radiation emitted therealong, which method comprises presenting an article to be identified to an emitted radiation path, detecting any interference to the path and determining whether such interference is representative of the known characteristic and, if so, the identity of the article.

In accordance with a second aspect of the invention, there is provided apparatus for identifying an article with a known characteristic capable of interfering with a path of radiation emitted therealong, which apparatus comprises means for presenting an article to be identified to an emitted radiation path, means arranged to detect any interference to the path and means for determining whether such interference is representative of the known characteristic of the article and, if so, the identity of the article.

Preferably, the apparatus also includes means for generating said emitted radiation path.

A third aspect of the invention resides in a method of identifying articles with a known characteristic capable of interfering with radiation, wherein the method comprises successively presenting a plurality of articles to a path of radiation, detecting for each successive article any interference with the path and determining whether any such interference is representative of the known characteristic of an article to be identified.

A further, fourth aspect of the invention provides apparatus for identifying articles with a known characteristic capable of interfering with radiation, the apparatus comprising means for providing a path of radiation, means for presenting successive articles to the radiation path, means for detecting any interference caused by each successive article upon the radiation path and means arranged to determine whether any such interference is representative of the known characteristic of an article to be identified.

Preferably, the radiation path is a narrow beam, possibly, collimated, generated by a light emitting diode (LED) or a semiconductor laser, whereby the radiation can be visible light or in the infra-red region of the spectrum. Of course, any other suitable radiation generator or emitter may also be used as an alternative.

Also, the detection means may comprise a phototransistor, preferably provided with an input lens for coping with very narrow beams of, say, infra-red radiation.

As indicated above, although infra-red and visible light emitters or generators and detectors may be used, other types of radiation emitters or generators and detectors can be employed, depending upon the part icular requirements of the inventive methods and apparatii desired.

In a preferred embodiment of the invention, a first radiation detector is in a direct line-of-sight with the radiation path, that is, it lies upon it directly facing the radiation emitter or generator, with a second radiation detector located at a critical angle to the radiation path, such that, when the known characteristic of an article to be identified interferes with the radiation path, any radiation deflected or otherwise deviated therefrom is detected by the second detector.

Such interference is advantageously by way of a given dimension, that is to say, the known characteristic, of the article partially interrupting or obstructing the radiation path, so that the radiation in that part of the path which is not interrupted or obstructed continues on to the first detector where the radiation received thereby is analysed to determine whether the interruption or obstruction of the radiation path is representative of the known characteristic of the article to be identified.

The remainder of the radiation, namely, that which has been deflected from the path by the known characteristic, is received by the second radiation detector and may be used to confirm detection by the first detector or as a primary detector in its own- right.

In the particular case of coin identification, the characteristic in question may be a dimension of the coin, for instance, its diameter or thickness.

Alternatively, it could be a milled edge of the coin, constituting a given surface structure with, say, a predetermined spacing between adjacent milled peaks.

Preferably, an electric output voltage is generated by at least the first radiation detector, which may be applied to comparator means, to determine whether the detected characteristic is the correct one and, hence, whether the correct article is identified.

Such identification may then be used to cause another operation to carried out upon the correctly identified article. For instance, in coin sorting methods and apparatii, such as that disclosed in co-pending Patent Application Number 8709297 (Publiaction Number filed on 16th April 1987 in the name of the present inventor, Leonard Marmaduke Steele, and entitled "Coin Sorting Apparatus", a signal representing the correct coin identification, namely, that for the correct coin denomination, may be used to cause the coin to be ejected from the associated coin sorting apparatus.

A similar arrangement may be used in conjunction with, say, a second radiation detector, as described above, wherein such a detector can be used in combination with the first radiation detector or in its own right as a primary detector.

The inventive methods and apparatii can have the ability to differentiate between, say, a coin of known denomination to be identified, that is to say, a coin of known diameter, and other denomination coins which are either oversize or undersize, at least insofar as their diameters are concerned.

Also, the various aspects of the invention may be employed to distinguish between coins to be identified and moving components of any associated coin sorting apparatus which may present themselves in the vicinity of the radiation path or beam, to at least partially interfere therewith, usually by obstructing such path.

In such an instance, as well as one involving an oversize or undersize coin, an associated ejector mechanism of the coin sorting apparatus is not actuated, so that the coins of incorrect denomination are moved ' further along the sorting apparatus, until they reach their respective ejector stations at which corresponding inventive identification apparatii are located.

In yet a further, fifth aspect of the invention, when used to identify coins with milled edges, a slit, whose width corresponds substantially with the spacing between adjacent milled peaks on the edge of a coin to be identified and which is generally parallel to such milling, is placed between the radiation path or beam and any second detector, so that any radiation deflected thereto has to pass through the slit. This provides a strobe effect between the radiation received by the first and second detectors and, hence, their respective output signals, which can be monitored to determine whether or not the correct denomination coin has been identified. This arrangement can provide alternative or additional identification of a coin of the correct denomination.

In order that the invention may be more fully understood, a preferred embodiment of coin identification apparatus and an associated method, in accordance therewith, will now be described by way of example and with reference to the accompanying drawings in which: Fig. 1 is a partial plan view of coin sorting apparatus with which inventive coin identification apparatus is associated; Fig. 2 is a side elevation of part of the coin sorting apparatus shown in Fig. 1, illustrating the inventive apparatus identifying a coin of the correct denomination; Fig. 3 is the apparatus of Fig. 2 but identifying an oversize coin; Fig. 4 is a front elevation of another part of the inventive apparatus showing a slit used for identifying coins with milled edges; Fig. 5 is a block circuit diagram of a signal processing circuit of the inventive apparatus; and Fig. 6 is a series of output waveforms for various points in the circuit shown in Fig. 5.

Referring firstly to Fig. 1 of the drawings, coin sorting apparatus, such as that disclosed and described in the co-pending patent application mentioned above, comprises a fixed support plate 1 which is inclined at an angle of approximately 45C to the horizontal and upon which are mounted three, freelyrotatable jockey wheels 2 rotatably supporting a ring 3 with a plurality of pear-shaped recesses 4 spaced equally around the periphery thereof. A rotatably drivable disc 5 is supported above the ring 3, with the latter being rotatable by the disc 5 by means of respective sets of meshing gear teeth 9,10 and a gear wheel 11 ' secured to the underside of the disc 5.

Coins of different denominations, and hence different diameters, are receivable in the recesses 4, having been fed thereto from apertures 7 around the periphery of the disc 5, under gravity.

Located around and adjacent the lower region of the ring 3 is a plurality of coin identification stations 16 at which are positioned respective coin outlet chutes A to G. Associated with each such station 16 is coin identification apparatus, in accordance with the invention and as shown generally at 101 in Figs.

2 and 3 of the drawings, together with a coin ejector (not shown), for instance, of the solenoid type, which is mounted behind the support plate 1 and which is actuable, when the associated coin identification apparatus 101 identifies a coin of the correct denomination by a known characteristic thereof, in this case, its diameter, to eject the identified coin from its corresponding recess 4 into the respective outlet chute A-G.

The coin identification apparatus 101 shown in Figs. 2 and 3, comprises a radiation emitter in the form of an infra-red emitting semiconductor laser 102 which can emit infra-red radiation upwardly in a narrow collimated path through an aperture 105, preferably slotted, in the support plate 1 of the coin sorting apparatus of Fig. 1.

A first, radiation detector in the form of a photo-transistor 103 is arranged directly in line and above the semiconductor laser 102, on the other side of the aperture 105, to receive infra-red radiation directly from the laser 102.

At a critical angle. of 90C to the radiation path between the semiconductor laser 102 and the phototransistor 103 is arranged a second, radiation detector, also above the laser 102 and on the opposite side of the aperture 105 thereto, in the form of a photo-transistor 104.

With particular reference to Fig. 2, when a coin 200 of the correct denomination, and hence diameter, for that station 16 is moved around in its associated aperture 4 of the ring 3, to be presented to the identification apparatus 101, it partially interferes, that is, obstructs, the infra-red radiation path between the laser 102 and the photo-transistor 103, due to the critical positioning of those apparatus components with respect to not only each other but also the related components of the coin sorting apparatus. In this manner, some of the infra-red radiation continues directly along the path to the photo-transistor 103, whilst the remainder, or at least some thereof, is reflected from the edge of the coin 200 to be received subsequently by the other photo-transistor 104 at right angles to the original infra-red radiation path.

The radiation reflected to the photo-transistor 104 is, in this case, reflected from the peaks of the milled edge of the coin 200, although it is possible for some radiation to be reflected from the other, lower regions of such milling, depending upon the orientation of the components involved. Thus, it is to be appreciated that the amount and actual waveform of the reflected radiation depends, at least to a certain extent, upon the nature of the surface structure of the edge of the coin 200.

An output signal is generated by the phototransistor 103, which is fed - to the circuit shown in Fig. 5. Here, the voltage signal from the photo-transistor 103 is fed to comparators 111,112 which, in turn, provide an output Y, as shown in Fig. 6, representative of the identification of the coin 200 of the correct denomination (diameter). This is also manifested at the output of a WAIT monostable M, as shown in Fig. 5, and as a square pulse waveform Y' (Fig. 6).As a result, an OUTPUT monostable N exhibits an output pulse Y'' which is fed to a LOGIC circuit 113, to provide a negative COIN VALID pulse Y''' which, in turn, is fed to a control circuit 114 arranged to actuate the coin ejector, subject to suitable comparison with an output voltage from the photo-transistor 104 which is depe,ndent;upon the presence of reflected radiation, or a strobe effect as described below, and generated by such radiation reflected from the milled coin edge.

Because the output pulse Y, which represents the shape of the portion of the coin 200 obstructing the radiation path, falls between two reference voltages REF1 and REF2, as shown in Fig. 6, as a consequence of the coin 200 of the correct denomination being identified, the COIN VALID pulse Y''' is generated, to actuate the ejector and eject the coin into the respective chute A-G, subject to proper comparison with the output from the second, photo-transistor 104, as mentioned above.

As the coin feed disc 5 and the ring 3 rotate, the infra-red radiation path between the laser i02 and the photo-transistor 103 is intermittently being obstructed completely by components of the coin sorting apparatus.

Under such conditions, the voltage outputs from the photo-transistor 103, as applied to the comparators 111,112, exceed both reference voltages REF1 and REF2, as shown in Fig. 6, these over-voltages being represented by the pulses X which cause an INHIBIT monostable L to be triggered, thus inhibiting the coin ejector (not shown). Such pulses are shown at X , X' and X'' for the respective INHIBIT, WAIT and OUTPUT monostables L, M and N.

In a similar manner, an oversize coin 300, as shown in Fig. 3, namely, one of the incorrect denom ination and larger than required diameter, when presented to the apparatus 101, inhibits actuation -of the coin ejector, thus proceeding further around the sorting apparatus until it reaches its associated station 16.

An undersize coin, that is, one whose diameter is less than that of a coin of the correct denomination, which is presented to the identification apparatus 101, will not cause the infra-red radiation path to be obstructed at all, so that the voltage output from the phototransistor 103 is not greater than that of REF2 and, hence, the ejector actuation is again inhibited, so that the undersize coin continues to the next station 16 for identification.

Thus, when a coin of the correct denomination is identified, the photo-current produced by the phototransistor 103 provides a voltage which is within the analogue section REF1/REF2 of the associated control circuit. However, when a component of the apparatus or an oversize coin completely obstructs the radiation path or when an undersize coin causes no obstruction of that path, the photo-current generated voltage at the photo-transistor 103 either exceeds or is less than, as the case may be, the analogue parameters of the circuit which, as a consequence, inhibits actuation of the ejector.

Another feature or aspect of the invention is illustrated in Fig. 4, wherein, in front of the phototransistor 104, is mounted an.arrangement which provides an adjustable slit S of width W set to correspond with the spacing between adjacent peaks of the milling on the edge of a coin to be identified. In this manner, a pronouncedstrobe effect can be produced between the radiation received by both photo-transistors 103,104, which is dependent upon such spacing and which can be monitored to differentiate between coins of different denominations having correspondingly different milled peak spacings.

Thus, for instance, if the width of the slit S is set for a particular coin denomination with a given or known milled peak spacing and a coin of a different denomination and peak spacing, or even no milled edge at all, is presented to the apparatus 101, then the difference between the two strobe signals or, as the case may be, the total lack of any such strobe effect, is monitored and used to identify the coins with the incorrect denominations.

This arrangement can be used to confirm that the correct denomination coin has been identified or, indeed, can be used for primary recognition or identification of coins.

Also, as the output pulse Y from the phototransistor 103 is modulated at a frequency corresponding to the milled edge peaks of a coin, this can be used to confirm identification of the coin, without involving the confirmatory signal from the photo-transistor 104.

It is to be understood that, although apparatus described above in relation to the accompanying drawings1 uses an inventive apparatus and method which rely upon a known dimension of a coin, namely, its diameter, obstructing the radiation path, other characteristics of articles may be employed to interfere in other ways with the radiation path, for instance, by induction or the like.

Claims (33)

1. Apparatus for identifying an article with a known characteristic capable of interfering with a path of radiation emitted therealong, which apparatus comprises means for presenting an article to be identified to an emitted radiation path, means arranged to detect any interference to the path and means for determining whether such interference is representative of the known charateristic of the article and, if so, the identity of the article.

2. Apparatus as claimed in claim 1 including means for generating the emitted radiation path.

3. Apparatus for identifying articles with a known characteristic capable of interfering with radiation, which apparatus comprises means for providing a path of radiation, means for presenting successive articles to the radiation path, means for detecting any interference caused by each successive article upon the radiation path and means arranged to determine whether any such interference is representative of the known characteristic of an article to be identified.

4. Apparatus as claimed in claim 1, 2 or 3, wherein the radiation path is a narrow beam.

5. Apparatus as claimed in claim 4, wherein the narrow beam is collimated.

6. Apparatus as claimed in any preceding claim, wherein the radiation path is generated by a light emitting diode or a semiconductor laser.

7. Apparatus as claimed in any preceding claim, wherein the radiation is visible light or in the infrared region of the spectrum.

8. Apparatus as claimed in any preceding claim, wherein said detection means comprises a phototransistor.

9. Apparatus as claimed in any preceding claim, wherein said detection means has an input lens.

10. Apparatus as claimed in any preceding claim including a first radiation detector in a direct lineof-sight with the radiation path and a second radiation detector at a critical angle to the radiation path, the arrangement being such that, when the known characteristic of an article to be identified interferes with the radiation path, any radiation deflected or otherwise deviated therefrom is detected by the second detector.

11. Apparatus as claimed in claim 10 including means arranged to analyse radiation detected by the first and/or second radiation detector, to determine whether any interruption or obstruction of the radiation path is representative of the known characteristic of an article to be identified.

12. Apparatus as claimed in claim 11, wherein said analysis means comprises comparator means and the first and/or second radiation detector is arranged to generate an output voltage upon detection of radiation and to apply the voltage to said comparator means, to determine whether the detected characteristic is a correct one and whether the correct article has been identified.

13. Apparatus as claimed in claim 12 including means arranged to cause another operation to be carried out upon a correctly identified article, upon such correct identification thereof.

14. A method of identifying an article with a known characteristic capable of interfering with a path of radiation emitted therealong, which method comprises presenting an article to be identified to an emitted radiation path, detecting any interference to the path and determining whether such interference is representative of the known characteristic and, if so, the identity of the article.

15. A method of identifying articles with a known characteristic capable of interfering with radiation, which method comprises successively presenting a plurality of articles to be identified to a path of radiation, detecting for each successive article any interference with the radiation path and determining whether any such interference is representative of the known characteristic of an article to be identified.

16. A method as claimed in claim 14 or 15, wherein the path of radiation is provided as a narrow beam.

17. A method as claimed in claim 16, wherein the beam is collimated.

18. A method as claimed in any of claims 14 to 17, wherein the radiation path is generated by a light emitting diode or a semiconductor laser.

19. A method as claimed in any of claims 14 to 18, wherein the radiation is generated as visible or infra-red radiation.

20. A method as claimed in any of claims 14 to 19, wherein said detection means is provided by a phototransistor.

21. A method as claimed in any of claims 14 to 20, wherein said detection means is provided with an input lens.

22. A method according to any of claims 14 to 21, wherein a first radiation detector is located in a direct line-of-sight with the radiation path and a second radiation detector is located at a critical angle to that path.

23. A method as claimed in claim 22, wherein radiation detected by the first and/or second radiation detector is analysed, to determine whether any interruption or obstruction of the radiation path is representative of the known characteristic of an article to be identified.

24. A method as claimed in claim 23, wherein, upon detection of radiation, the first and/or second radiation detector generates an output voltage which is applied to comparator means, to determine whether the detected characteristic is a correct one and whether the correct article has been identified.

25. A method as claimed in claim 24, wherein another, subsequent operation is carried out upon a correctly identified article, upon correct identification thereof.

26. A method of identifying an article with a known characteristic capable of interfering with a radiation path substantially as hereinbefore described.

27. A method of identifying coins according to a method as claimed in any of claims 14 to 26.

28. A method of identifying coins with milled edges in accordance with claim 27, wherein a slit whose width corresponds substantially with the spacing between adjacent milled peaks on the edge of a coin to be identified, is placed between the radiation path and any second radiation detector and generally parallel to said milling, whereby any radiation deflected from the radiation path to the second detector by the coin passes to that detector through the slit, to provide a strobe effect between the radiation received by any first radiation detector and the second radiation detector.

29. A method as claimed in claim 28, wherein respective outputs from the first and second detectors are monitored, to determine whether or not the correct denomination coin has been identified.

30. Apparatus for identifying coins with milled edges, as claimed in any of claims 1 to 13, wherein a slit with a width corresponding substantially to the spacing between adjacent milled peaks on the edge of a coin to be identified, is arranged between the radiation path and any second radiation detector generally parallel to said milling, such that any radiation deflected from the radiation path to the second detector passes to that detector through the slit, to provide, in use, a strobe effect between radiation received by any first radiation detector and the second radiation detector.

31. Apparatus as claimed in claim 30 including means for monitoring respective outputs from the first and second detectors, to determine whether or not the correct denomination of coin has been identified.

32. Apparatus for determining the denomination of coins, substantially as hereinbefore described with reference to the accompanying drawings.

33. Coin sorting apparatus incorporating coin denomination identification apparatus as claimed in any of claims 1 to 13 and claims 30 and 31.