Currency validation apparatus and method

1. A method of validating articles of currency, comprising:

checking, prior to determining whether or not the article is to be accepted or rejected, the measured properties of an article against a plurality of sets of criteria, each set corresponding to a predetermined type of article;

determining whether the article is a valid type of one of the predetermined types and issuing a signal indicative of whether the article is to be accepted or rejected; and

subsequently determining whether the measured properties meet at least one further set of criteria of an article of a different type,

wherein the combination of sets which are checked prior to issuing the signal is altered.

2. A method as claimed in claim 1 , wherein altering the combination is performed in response to determining that the measured properties meet a further one of the sets of criteria, and wherein the act of altering results in that further set of criteria being checked, in a subsequent validation operation, prior to issuing the signal.

3. A method as claimed in claim 2 wherein the act of altering results in that further set of criteria being checked in a next validation operation prior to issuing the signal.

4. A method as claimed in claim 1 , wherein the act of altering includes altering the combination in a manner determined by which sets of criteria have been met in a plurality of previous validation operations.

5. A method as claimed in claim 1 , wherein the act of altering includes causing a plurality of further sets of criteria, associated with a plurality of currency articles of a common currency, to be included within the sets which are checked prior to issuing the signal.

6. A method as claimed in claim 1 , wherein the act of altering comprises causing one of the further sets of criteria to be considered prior to issuing the signal, and causing one of the first-mentioned sets criteria to be considered after the signal is issued.

7. A method as claimed in claim 6 , wherein the act of altering is capable of causing any of the first-mentioned sets to be considered after issuing the signal.

8. A method of validating articles of currency, comprising:

checking, prior to determining whether or not the article is to be accepted or rejected, the measured properties of an article against a plurality of sets of criteria, each set corresponding to a predetermined type of article;

determining whether the article is a valid type of one of the predetermined types and issuing a signal indicative of whether the article is to be accepted or rejected;

subsequently determining whether the measured properties meet at least one further set of criteria of an article of a different type, and

storing data indicating the number of articles which have met at least one further set of criteria in such a manner as to enable downloading of the data.

9. A method of validating articles of currency comprising:

measuring properties of an article;

checking the properties against a plurality of sets of criteria, each set corresponding to a predetermined type of article; and

determining, as a result of the checking operation, whether the article is one of said types, wherein the criteria relating to respective types of articles are considered in a sequence, and the sequence is altered for a subsequent validation operation.

10. A method as claimed in claim 9 , including issuing a signal indicating that the article is not genuine after a plurality of determinations and depending on the results of those determinations, and prior to further determinations being made.

11. A method of validating articles of currency comprising:

measuring properties of an article;

checking the properties against a plurality of sets of criteria, each set corresponding to a predetermined type of article, during a validation period prior to issuing a signal indicating whether the article is an article of one of the predetermined types; and

automatically preventing a single one of the sets of criteria, associated with a predetermined type of article, from being considered during a validation period of a subsequent validation operation.

12. A method of validating articles of currency comprising:

measuring properties of an article;

checking the properties against a plurality of sets of criteria, each set corresponding to a predetermined type of article, during a validation period prior to issuing a signal indicating whether the article is an article of one of the predetermined types; and

automatically causing a single different set of criteria, associated with a different type of article, to be considered during a validation period of a subsequent validation operation.

13. Apparatus for validating articles of currency comprising:

memory for storing data defining a plurality of sets of criteria, each set corresponding to a predetermined type of article; and

a processor operable to compare measured properties of an article with the criteria, and further operable to permit the criteria to be rendered effective or ineffective and to increment a credit count if the article is of the predetermined type for which the criteria are effective,

wherein the apparatus is capable of responding to recognition of a single article of one of the predetermined types by automatically preventing one of the sets of criteria from being effective during a subsequent validation operation, and then preventing incrementing of the credit count for the predetermined type of article.

14. Apparatus for validating articles of currency comprising:

memory for storing data defining a plurality of sets of criteria, each set corresponding to a predetermined type of article; and

a processor operable to compare measured properties of an article with the criteria, and further operable to permit the criteria to be rendered effective or ineffective and to increment a credit count if the article is of the predetermined type for which the criteria are effective,

wherein the apparatus is capable of responding to recognition of a single article of one of the predetermined types by automatically enabling a set of criteria, to be effective during a subsequent validation operation, thus enabling incrementing of the credit count when the predetermined type of article is recognized.

15. A method of validating articles of currency comprising:

measuring properties of an article;

checking the measured properties against a plurality of sets of criteria, each set corresponding to a predetermined type of article, during a validation period prior to issuing a signal indicating whether the article is an article of a said predetermined type, the number of sets checked being substantially equal to the maximum possible to be checked during said validation period; and

wherein the method includes at least one of automatically preventing one of the sets from being considered during the validation period of a subsequent validation operation, and automatically causing a different set of criteria, associated with a different type of article, to be considered during the validation period of a subsequent validation operation.

16. A method of validating articles of currency comprising:

measuring properties of an article;

checking the measured properties against a plurality of sets of criteria, each set corresponding to a predetermined type of article and the predetermined types belonging to the same currency, during a validation period prior to issuing a signal indicating whether the article is an article of a said predetermined type; and

wherein the method includes at least one of automatically preventing one but not all of said sets from being considered during the validation period of a subsequent validation operation, and automatically causing a different set of criteria, associated with a different type of article of the same currency, to be considered during the validation period of a subsequent validation operation.