How Does a Typewriter Work?

A typewriter is a machine that prints letters or characters onto a sheet of paper. The first typewriter was patented in the United States in 1868. Portable typewriters didn't come about until the early 1900's. Electric typewriters, which increased the speed for the typist, came into use during the 1920's. Typewriters became a standard piece of office equipment, and were also purchased for homes, used by students and writers. By the 1980's some typewriters included memories, which allowed typists to type several sentences and check for errors, before the words were printed on the paper. Although this might seem as an innovation for the typewriter, it was also the era of the new and emerging home computer. Within a few years, the typewriter became an obsolete piece of equipment, often replaced by the home or office computer.

The traditional typewriter includes a keyboard, which consists of buttons that are called keys. The pattern of the typewriter keyboard is similar to the keyboard of the computer. One or two letters, symbols or numbers are marked on each key. The key is part of a lever which has a bar of type attached to the other end. The bar of type corresponds to what is written on its key. If a letter is marked on the key, the corresponding piece of type will have that letter as two characters, one lower case and one capitalized. The typewriter also has a rubber roll called a platen. A platen holds the paper in the typewriter. A sheet of paper can be inserted into the typewriter, and rolled into place. The typewriter also includes an ink ribbon or a carbon tape.

A sheet of paper is rolled into the typewriter. The typist hits a key, which makes the lever raise, pushing the bar of type against the ink ribbon and on the paper. The pressure of the bar of type pressing through the ink ribbon or carbon tape leaves an imprint on the paper. Since each key has two characters, typewriters need a way for the key to choose which of the letters to press on the paper. Shift mechanisms allow the typists to choose the second character on the key. Other levers on the typewriter add spaces to the line of type or help to move the paper up through the typewriter.

Not all typewriters have keys with letters. Later typewriters were often made with the raised type placed on balls or daisy wheels, that moved. In the traditional typewriter the platen moved along as the typists type, positioning the paper for the next key stroke. With the daisy wheel or ball, the platen remained stationary, while the wheel or ball moved along the line on the paper.