Typewriter keyboard with double shift mechanism - has three groups of keys each with three different symbols and shift keys locked in position

摘要

Typewriter keyboard with a double shift mechanism is designed to possess an increased type capacity although the number of keys remains practically unchanged and the number of necessary shifts for typing a certain text is strictly limited. This is achieved by having three groups of keys each with three symbols. The first group has in each case three of the same symbols arranged under one another, a second group has two different symbols while the third group has three different symbols. - The shift keys can be locked in the shift position by displacing them and are coupled to the space bar. The shift keys are placed one above the other in the centre of the keyboard.