Abstract: A keyboard for use with a terminal in a telephone operator assistance system is disclosed. The keyboard has a numeric array of keys that is surrounded on three sides by separate arrays of specialized function keys. The keyboard is arranged so that the most common keying sequence consists of the operation of a function key in the array to the left of the numeric array, the operation of keys in the numeric array, and the operation of a function key in the array to the right of the numeric array. This keyboard arrangement has been found experimentally to reduce operator work time. In addition, the keyboard contains a main array including alphabetic keys and miscellaneous function keys, and arrays of function keys to the left of and in back of the main array. The function keys are grouped in different arrays according to the type of function being performed, and the relationship of that function to the operation of keys in the numeric array.

Abstract: Apparatus for mounting a movable superstructure on a fixed base is disclosed. The superstructure, a video display unit, is attached to a cylindrical segment journal which rests on a matching cylindrical segment socket. The journal rotates within the socket as the video display unit is tilted back and forth. Two helical springs are each attached to the superstructure and the base in such a way as to counteract gravitational forces and to tend to restore the superstructure to a neutral tilt angle when it is moved therefrom. The surfaces of the journal and socket have enough friction to exceed the relatively small differences between the gravitational forces tending to move the superstructure further from the neutral tilt angle and the spring forces tending to restore the superstructure thereto. As a result, the superstructure will maintain any position but can be moved (tilted) by overcoming only the relatively small frictional force. In one constructed model, a video display unit superstructure weighing 27.