A variety of techniques and apparatus have been used to satisfy the requirements of automated currency handling machines. At the upper end of sophistication in this area of technology are machines which are capable of rapidly identifying, discriminating and counting multiple currency denominations. This type of machine, hereinafter designated as a "denomination discriminator," typically employs either magnetic sensing or optical sensing for identifying the denominations of bills in a stack and discriminating between different currency denominations. At a lower level of sophistication in this area are machines which are designed to rapidly count the number of currency bills in a stack, but which are not designed to identify or discriminate among multiple currency denominations. This type of machine, hereinafter designated as a "counter," may include magnetic or optical sensors sufficient to enable it to discriminate between acceptable and non-acceptable bills in a stack of bills having a known denomination, but typically do not permit the machine to identify the denomination of bills or discriminate among multiple denominations of currency. Consequently, counters known in the art do not typically "know" what denomination they are counting until they are informed of the particular denomination by an external signal or operator.
Whether employed in a denomination discriminator or counter, magnetic sensing is based on detecting the presence or absence of magnetic ink in portions of the printed indicia on the currency by using magnetic sensors, usually ferrite core-based sensors, and using the detected magnetic signals, after undergoing analog or digital processing, as the basis for discrimination. The more commonly used optical sensing technique, on the other hand, is based on detecting and analyzing variations in light reflectance or transmissivity characteristics occurring when a currency bill is illuminated and scanned by a strip of focused light. The subsequent currency discrimination is based on the comparison of sensed optical or magnetic characteristics with prestored parameters relating to different currency denominations, while accounting for adequate tolerances reflecting differences among bills of a given denomination. Similarly, the acceptance or rejection of a bill is based on the comparison of sensed optical or magnetic characteristics with prestored parameters defining an acceptable bill, while accounting for adequate tolerances reflecting differences among bills of a given denomination. An example of a currency handling machine using an optical scanning technique is described in U.S. Pat. No. 5,295,196, issued Mar. 15, 1994 to Raterman et al. and assigned to Cummins-Allison Corporation, incorporated herein by reference.
Currency handling machines (e.g. denomination discriminators or counters) known in the art typically include a system memory for storing prestored parameters associated with the magnetic or optical characteristics of the various currency denominations to be evaluated or counted. The types or denominations of currency which a machine is able to accommodate is dependent on the prestored parameters with which it has been programmed. For example, a machine designed for U.S. markets must be programmed with prestored parameters associated with magnetic or optical characteristics of U.S. currency, while a machine designed for a foreign market must be programmed with prestored parameters associated with the appropriate foreign currency. A machine designed for one market will be unable to accommodate currency from the another market unless it has been encoded with the appropriate prestored parameters for that other market. Additionally, once programmed with the appropriate prestored parameters, the system memory must be updated or supplemented periodically in order to reflect the most recent optical or magnetic characteristics of the various currency denominations to be evaluated, which may occur, for example, upon the issuance of a new series of bills.
Heretofore, the encoding or updating of prestored parameters into the system memory of discrimination machines or counters have been accomplished externally from the machine, typically at a factory or service center. For example, in discrimination machines employing memory chips such as erasable programmable read only memorys (EPROMs), the chips are typically programmed or updated at the factory or service center and either installed in the machine at the factory or, in the case of updates, shipped to the customer for re-installation in the machine. An alternative method of encoding or updating prestored parameters may be utilized in discrimination machines employing "flash card" technology, such as described in U.S. patent application Ser. No. 08/715,029, now issued as U.S. Pat. No. 5,909,502, assigned to the assignee of the present invention and incorporated herein by reference. In such a "flash card" loading system, a flash card is programmed with the desired code and the machine may be encoded or updated by inserting the flash card into the machine, causing the system memory to become replaced with the flash card memory. Nevertheless, in either of the above prior systems, the source of the code is external to the machine, typically at the factory or service center level, and the discrimination capability of a particular machine is limited to only those bills associated with the pre-stored parameters with which it has been programmed.
Accordingly, in view of the above-described problems, there is a need for a currency handling system that is able to accommodate currencies of several denominations and types without having been externally programmed or updated with pre-stored parameters associated with those denominations and types. Similarly, there is a need for a note counter which is able to determine the denomination of currency it is counting without having been informed of the denomination by an external signal or operator. The present invention is directed to satisfying or at least partially satisfying these needs.