Optical recognition system for capsules for the production of hot beverages

Abstract

A method for the optical recognition of capsules for hot beverages machines comprises the steps of introducing a capsule in a machine, stimulating the capsule by an exciting optical signal emitted by a light source, reading a feedback optical signal by an optical reader, acquisition of the values of the frequency and/or the time frame of the feedback optical signal, determining the fulfillment of predetermined conditions on the values of the frequency and/or the time frame. On the basis of the step of evaluating there is then a step of blocking the normal operation of the machine or a step of pursuing the normal operation of the machine.

Claims

1. A method for optical recognition of a capsule for a hot beverage machine, a comprising the steps of: providing that the capsule is marked with a recognition substance, wherein, in response to an excitation by an optical signal at a first predetermined frequency and to a first predetermined time frame, the recognition substance is arranged to emit an optical signal at a second predetermined frequency for a second predetermined time frame; introducing the capsule into the hot beverage machine; stimulating the capsule with an exciting optical signal emitted by a light source of the hot beverage machine, the exciting optical signal being emitted at the first predetermined frequency and for the first predetermined time frame; reading a feedback optical signal by an optical reader of the hot beverage machine, the feedback optical signal being emitted by the capsule at the second predetermined frequency and for the second predetermined time frame; acquiring values of at least one chosen from the second predetermined frequency and the second predetermined time frame of the feedback optical signal; evaluating, with a control unit of the hot beverage machine, a fulfillment of predetermined conditions on the values of the at least one chosen from the second predetermined frequency and the second predetermined time frame of the feedback optical signal; blocking a normal operation of the hot beverage machine if the evaluating is negative; pursuing the normal operation of the hot beverage machine if the evaluating is positive; providing that the recognition substance is located inside the capsule.

2. The method according to claim 1, and further comprising piercing the capsule to carry out the steps of stimulating and reading.

3. The method according to claim 2, and further comprising performing the piercing with a perforation unit comprising at least one light guide.

4. The method according to claim 2, wherein the step of evaluating is positive if the feedback optical signal is emitted at the second predetermined freguency.

5. The method according to claim 2, wherein the step of evaluating is positive if the feedback optical signal is emitted for the second predetermined time frame.

6. The method according to claim 2, and further comprising a step of recognizing the capsule wherein the control unit detects a plurality of features of the capsule on a basis of the step of acquiring the values of at least one chosen from the second predetermined frequency and the second predetermined time frame of the feedback optical signal.

7. The method according to claim 2, wherein the first and second predetermined frequencies are different from each other and belong alternatively: to the visible range; to the UV range; to the infrared range.

8. The method according to claim 2, wherein the first predetermined frequency belongs to the UV range and the second predetermined frequency belongs to the visible range.

9. The method according to claim 1, and further comprising producing the capsule, comprising the steps of: prearranging a main body of the capsule; filling the main body with a predetermined food substance; introducing the recognition substance, via a permeable support element, in the main body; sealing the main body with a sealing film.

10. The method according to claim 9, wherein at least one chosen from the sealing film and the main body comprises at least one portion transparent to the exciting optical signal emitted during the stimulating and to the feedback optical signal emitted during the reading.

11. The method according to claim 1, wherein the step of evaluating is positive if the feedback optical signal is emitted at the second predetermined frequency.

12. The method according to claim 1, wherein the step of evaluating is positive if the feedback optical signal is emitted for the second predetermined time frame.

13. The method according to claim 1, and further comprising a step of recognizing the capsule wherein the control unit detects a plurality of features of the capsule on a basis of the step of acquiring the values of at least one chosen from the second predetermined frequency and the second predetermined time frame of the feedback optical signal.

14. The method according to claim 1, wherein the first and second predetermined frequencies are different from each other and belong alternatively: to the visible range; to the UV range; to the infrared range.

15. The method according to claim 1, wherein the first predetermined frequency belongs to the UV range and the second predetermined frequency belongs to the visible range.

16. A system for recognizing a capsule for a hot beverage machine, the system comprising: a hot beverage machine comprising: a light source arranged to emit an exciting optical signal at a first predetermined frequency and for a first predetermined time frame; an optical reader arranged to read a feedback optical signal emitted at a second predetermined frequency and for a second predetermined time frame; a capsule configured to be inserted in the machine, the capsule including a recognition substance located in an interior of the capsule; the hot beverage machine arranged to emit the exciting optical signal into the interior of the capsule and to read the feedback optical signal emitted from the interior of the capsule; a control unit arranged to block a normal operation of the hot beverage machine if values of at least one chosen from the second predetermined frequency and the second predetermined time frame do not meet predetermined conditions.

17. The system according to claim 16, wherein the control unit is further arranged to pursue the normal operation of the hot beverage machine if the values of the at least one chosen from the second predetermined frequency and the second predetermined time frame do meet predetermined conditions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further characteristic and/or advantages of the present invention are more bright with the following description of an exemplary embodiment thereof, exemplifying but not limitative, with reference to the attached drawings in which:

(2) FIG. 1 shows a diagrammatical view of the method for the optical recognition of capsules, according to the present invention;

(3) FIG. 2A diagrammatically shows the step of stimulating the capsule operated by a dichroic mirror;

(4) FIG. 2B diagrammatically shows the step of reading the feedback optical signal operated by a dichroic mirror;

(5) FIG. 3A shows, in cross section, a first exemplary embodiment of the step of piercing the capsule inside marked;

(6) FIG. 3B shows, in cross section, a second exemplary embodiment of the step of piercing the capsule inside marked;

(7) FIG. 3C shows, in cross section, a third exemplary embodiment of the step of piercing the capsule inside marked;

(8) FIG. 3D shows, in cross section, a fourth exemplary embodiment of the step of piercing the capsule inside marked;

(9) FIG. 4 shows, in cross section, an exemplary embodiment of of the steps of stimulation and reading that provides sealing film;

(10) FIG. 5 graphically shows the trend with time of the exciting optical signals and of the feedback optical signal using two different recognition substances.

(11) Description of a preferred exemplary embodiment In FIG. 1 a diagrammatical scheme 300 is shown that describes, according to the present invention, a possible embodiment of the steps of the method for the optical recognition of capsules 100 for hot beverages machines.

(12) After a first step of introducing the capsule 100 in the machine [301], there is a step of stimulating the capsule 100, wherein a light source 210 emits an optical signal with a predetermined frequency f.sub.1A and for a predetermined time frame t.sub.1H [302].

(13) If the capsule 100 is remarkable with the predetermined recognition substance, it will respond to the optical signal received emitting a feedback optical signal at a frequency f.sub.2B for a time frame t.sub.2K.

(14) In a preferred embodiment, the recognition substance has fluorescence properties, i.e. capable of re-transmitting an optical signal consisting of visible frequencies when it is excited with an optical signal having frequencies in the ultraviolet range.

(15) In this exemplary embodiment, with reference even at FIGS. 2A and 2B, the machine has a dichroic mirror 230 arranged to result transparent to the optical frequencies of the visible range (black arrows) and to reflect the optical frequencies of the UV range (white arrows). This way, it is possible to use also low cost light sources 210, which normally emit light signals that in addition to the required frequencies UV contain also some unwanted visible frequencies. In this case, when the light source 210 will emit an optical bright signal comprising both visible and UV frequencies, only the UV ones are reflected towards the capsule 100, causing excitation.

(16) The feedback optical signal is a signal comprising both the predetermined visible frequencies and the UV frequencies reflected and not converted by the recognition substance. With reference to FIG. 2B, again the mirror dichroic 230 is transparent to the visible frequencies and it will reflect the UV frequencies, sending back them towards the source 210. Only the visible frequencies will then arrive to an optical reader 220 that will initiate a step of reading the signal itself [303]. The fact that the parasite UV frequencies are removed by the feedback optical signal ensures to the optical reader 220 a reading enough accurate also in case that you use a low cost reader.

(17) The source 210 and/or the optical reader 220 need not necessarily to be located near the capsule 100. The exciting and feedback optical signals can be transported by respective optical fibers or, advantageously, by a single optical fiber used in both the directions.

(18) In another preferred exemplary embodiment, the recognition substance has phosphorescent properties, and it is therefore arranged to send back a feedback optical signal that extends in time after the turning off of the exciting optical signal, normally for several millisecond. In this case, the optical reader 220 can start the step of reading the feedback optical signal only after that the exciting signal has been interrupted, avoiding interferences of unwanted reflected frequencies, without the need of using the dichroic mirror. Such exemplary embodiment is therefore cheaper than the previous.

(19) After a step of acquiring the values of the frequency f.sub.2 and of the time frame t.sub.2 of the feedback optical signal [304], a control unit starts a step of evaluating the fulfillment of predetermined conditions on such values [305]. If the capsule 100 was a capsule correctly marked, the values of f.sub.2 and t.sub.2 will satisfy the above described conditions, allowing the machine to proceed with its correct operation. Otherwise, the machine will be blocked, avoiding the production of the hot beverage.

(20) For example, in an exemplary embodiment previously described, where it is used a recognition substance with phosphorescent properties, the control unit can evaluate the law with which there is the decay with time of the feedback optical signal and test if the decay time respects or not predetermined conditions. Such procedure can allow then to transmit a large number of information by appropriately changing the recognition substance and then the decay time of the feedback optical signal. In this case, the frequency of the exciting signal f.sub.1 can coincide with the frequency f.sub.2 of the feedback signal.

(21) In FIG. 4 is graphically shown the typical trend with time of the exciting and feedback optical signals. In particular, given a step exciting signal having a time frame t.sub.1, can be to seen as two different substances A and B emit a feedback signals with different time frames t.sub.2A and t.sub.2B. Such, as above said, allows distinguishing the substances to each other.

(22) In the FIGS. 3A, 3B, 3C and 3D, are shown some possible exemplary embodiments of the step of piercing the capsule 100 for carrying out the steps of stimulating and reading.

(23) In the FIGS. 3A and 3B the unit that provides to the steps of stimulating and reading the substance located within the capsule 100 implements even the perforation of the capsule, regardless of the perforator, not shown and located in another desired point, arranged to introduce pressurized hot water in the production process for the hot beverage.

(24) In the FIGS. 3C and 3D the unit that provides to the steps of stimulating and reading the substance located within the capsule is instead housed inside of the same perforator 255 arranged to introduce pressurized hot water in the production process for the hot beverage.

(25) For mere exemplifying purposes, the recognition substance located inside has a ring shape in FIGS. 3A and 3B and a point-shaped shape in FIGS. 3C and 3D.

(26) In particular, in FIG. 3A the perforation unit 250 comprises two separate light guides 251, consisting of two glass or plastic perforating rods, in optical connection with the relative components located at short distances.

(27) In FIG. 3B the perforation unit 250 comprises instead a single light guide 251 comprising a single glass or plastic perforating rod, in optical connection with the respective lighting/reading components, thanks to a suitable splitter of the two signals.

(28) In FIG. 3C the perforation unit 250 comprises two separate light guides 251, housed within the punch pin 255 arranged to introduce the hot water, which allow to house the components of lighting/reading on the main electronic board, which is located in remote.

(29) In FIG. 3D the perforation unit 250 comprises a single optical fiber 251, housed within the punch pin 255 arranged to introduce the hot water, and a suitable splitter of the 2 signals mounted on the main electronic board, which is located in remote.

(30) In FIG. 4 the capsule 100 comprises a film 130 having at least one transparent portion. In this exemplary embodiment, the steps of stimulating and reading the inner marker are made through the light source 210 and the optical reader 220, without needing to perforate the film 130 itself.

(31) In this exemplary embodiment, the light source 210 and the optical reader 220 can be separated by a barrier 215 arranged to be placed in contact with the transparent portion 130 in order to prevent that, in case of introducing a not suitable capsule having an illicit recognition substance located on the outer surface of the film 130, the feedback optical signal can reach the optical reader 220.

(32) The foregoing description some exemplary specific embodiments will so fully reveal the invention according to 20 the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt in various applications the specific exemplary embodiments without further research and without parting from the invention, and, accordingly, it is meant that such adaptations and modifications will have to be considered as equivalent to the specific embodiments. The means and the materials to realize the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is to be understood that the phraseology or terminology that is employed herein is for the purpose of description and not of limitation.