Postal Equipment

devices and means of transport used in the principal postal operations, including collection of mail, issue, sorting, transport, and delivery.

The simplest postal device, the letter box, was proposed by the Frenchman Renoir de Villays in 1653. The first specialized mail carriage, the stagecoach, came into use in the 16th century. In the early 19th century the coach was replaced by the horse-drawn rail carriage. After the Liverpool-Manchester railroad line was opened in Great Britain in 1830, railroad transport of mail began. The mail was initially transported as freight, but in 1839 postal authorities began using mail cars specially equipped for processing correspondence in transit. The rapid growth of postal transport in the 19th and 20th centuries was due to the development of railroads, water transport, motor vehicles, and air transport.

Postal equipment is classified according to the basic types of postal operations. In the USSR, the Onega postal cash registering machine system has been used since 1971 in receiving and issuing mail at main and branch post offices; as of 1974, more than 1,300 of these machines were in operation. The machines are used to register the acceptance and payment of money orders, the receipt of insured letters and mailing wrappers with statements of value, and the receipt of parcels, telegrams, and so forth; the machines issue receipts and keep a record of operations. A perforator is used to record data about received and paid postal and telegraphic money orders on a telegraphic punched tape; a data communications device transmits the data by communications channels to zonal computer centers to compare automatically accepted and paid money orders. In cities having computer centers, the punched tape is delivered directly to the centers. Postal cash registering machines increase the labor productivity of postal operators in cash operations by 1.5–2 times. A network of automated postal centers exists in towns and resort settlements; these centers sell envelopes, postcards, and newspapers and allow one to send a registered letter and obtain a receipt for it by means of an automatic machine; 160 automated postal centers were in operation in early 1973.

Postal-processing machines are.used to handle parcels, letters, mailing wrappers, newspapers, and magazines. Large mail centers use semi-automatic machines to sort mail and also have belt and chain conveyors to transport and distribute sacks, newspaper bundles, and containers with parcels and letters to processing areas. Experimental models of automatic letter-processing machines appeared in the 1960’s, and automated letter-processing lines were introduced in the early 1970’s at large postal sorting centers in the Federal Republic of Germany, Japan, the USA, France, Great Britain, and other countries. In these centers, the letters removed from the letter boxes are emptied into the receiving hopper of a sorting machine at the head of a production line. Mechanical analyzers enable the machine to separate standard-size letters and cards from the non-standard ones. The standard-size correspondence is fed into a facer-canceler, which aligns the letters with respect to address and postage stamp, postmarks the letters, and cancels the stamps. The letters are then fed directly either to an automatic letter-sorting machine in special holders or to coding devices that first convert the numerical or letter address into a conditional code composed of luminescent dots or lines and then direct the letters to the automatic letter-sorting machine. A reading device in the automatic letter-sorting machine reads the coded information concerning the postal address, and the letter or card is sent to the appropriate accumulator. Automatic lines have a capacity of 20,000 letters per hour. As of 1974, the USSR had developed automatic lines similar to those described above, differing only in that the address side of the envelope is always recognized directly; stylized numerals written on the envelope by the sender serve as a six-character address code that is read by the automatic letter-sorting machine.

For the transport of letters within postal facilities, postal installations use conveyors that are equipped to address boxes of letters and automatically unload them according to the addresses on the containers.

Parcels are sorted according to destination by semiautomatic sorting machines, consisting of a distributing conveyor, accumulators, and a keyboard. The operator assigns the address— the place of discharge to the accumulator—from a control panel by means of mechanical or electronic control and storage devices. These machines have a straight-line or other form of distributing conveyor and a chain or belt hauling unit. The machines sort 900–1,500 parcels per hour per operator. A machine having a distributing conveyor with a vertical closed-loop chain drive is used for sorting small parcels and mailing wrappers. Hinged on the chain for its entire length are platforms on which small parcels and mailing wrappers are transported to two types of accumulators: hoppers located on both sides of the machine and small carts under the machine. The machine handles up to 200 sorting routes and has a capacity of 1,200 parcels per hour per operator.

All modern types of air, land, and water transport are used for carrying mail. The early 1970’s saw the development of containerized mail transport by specialized railroad mail cars and self-loading motor vehicles in the USSR and a number of other countries. Railroad mail cars are equipped with extension-type crane booms, sliding doors, a crane and door remote control panel, and a self-contained power-supply system. This type of car can carry up to 45 containers, with each container weighing up to 500 kg when filled.

In 1971, the USSR began using a system in which motor vehicles are used to deliver mail to central distribution points. These points are metal cabinets that have small locking doors and are mounted on the floor or fastened to a wall. The mailman takes mail from the cabinets and delivers it to the addressees or places it in the addressees’ mailboxes, which are located in the entryways of residential dwellings.

The trend in postal technology is toward the adoption of automated processing systems for all types of mail and printed publications. There is likewise a trend toward the creation of automated production-process control systems both within large postal enterprises and in the postal service as a whole.