Post Office Sorting MachinesAs a result of this research, the first semi-automatic parcel sorting machine was introduced in Baltimore in 1956. A year later, a foreign-built multiposition letter sorting machine (MPLSM), the Transorma, was installed and tested for the first time in an American post office. The first American-built letter sorter, based on a 1,000-pocket machine originally adapted from a foreign design, was developed during the late 1950s. The first production contract was awarded to the Burroughs Corporation for 10 of these machines. The machine was successfully tested in Detroit in 1959 and eventually became the backbone of letter-sorting operations during the 1960s and 70s.
Post Office CancelersIn 1959, the Post Office Department also awarded its first volume order for mechanization to Pitney-Bowes, Inc., for the production of 75 Mark II facer-cancelers. In 1984, more than 1,000 Mark II and M-36 facer-cancelers were in operation. By 1992, these machines were outdated and began to be replaced by advanced facer-canceler systems (AFCS) purchased from ElectroCom L.P. The AFCSs process more than 30,000 pieces of mail per hour, twice as fast as the M-36 facer-cancelers. AFCSs are more sophisticated too: they electronically identify and separate prebarcoded mail, handwritten letters, and machine-imprinted pieces for faster processing through automation.
Post Office Optical Character ReaderThe Department's accelerated mechanization program began in the late 1960s and consisted of semi-automatic equipment such as the MPLSM, the single position letter sorting machine (SPLSM), and the facer-canceler. In November 1965, the Department put a high-speed optical character reader (OCR) into service in the Detroit Post Office. This first-generation machine was connected to an MPLSM frame and read the city/state/ZIP Code line of typed addresses to sort letters to one of the 277 pockets. Each subsequent handling of the letter required that the address be read again.
Mechanization increased productivity. By the mid-1970s, however, it was clear that cheaper, more efficient methods and equipment were needed if the Postal Service was to offset rising costs associated with growing mail volume. To reduce the number of mail piece handlings, the Postal Service began to develop an expanded ZIP Code in 1978.
The new code required new equipment. The Post Office entered the age of automation in September 1982 when the first computer-driven single-line optical character reader was installed in Los Angeles. The equipment required a letter to be read only once at the originating office by an OCR, which printed a barcode on the envelope. At the destinating office, a less expensive barcode sorter (BCS) sorted the mail by reading its barcode.
Following the introduction of the ZIP+4 code in 1983, the first delivery phase of the new OCR channel sorters and BCSs was completed by mid-1984.