Binary information display apparatus

Abstract

A binary information display apparatus displays braille information with high accuracy by means of four braille pins, which are actuated by a stepping motor having a stepping angle of 45.degree. and, hence, eight step positions. The apparatus includes four pins; a triplet cam which acts on ends of three pins out of the four pins so as to independently urge such three pins to selectively project from a display surface of a pin-supporting member and to selectively retract the same behind the display surface; a stepping motor for rotating the triplet cam about an axis thereof; and a fourth cam portion which actuates the remainder of the four pins. The motor can perform consecutive seven steps at 45.degree. intervals, starting from a position where a rotation restricting projection on the fourth cam portion abuts a stopper step surface on the pin-supporting member, without causing rotation of the fourth cam portion. The state of the fourth pin is therefore not changed during such consecutive stepping of the stepping motor over seven steps. With the above-described structural arrangements and resulting operations thereof, it is possible to display eight types of braille information. Similarly, eight types of braille information can be displayed by reversing the motor. Consequently, sixteen types of braille information can be produced by the apparatus of this invention.