| 摘要 |
An encoding device having a keyboard in which the depression of a key suddenly changes the amount of magnetic flux flowing through one of an array of magnetic core elements. Windings are arranged on each core element in a coded pattern, and the sudden flux change induces in the windings electrical output signals which are encoded in accordance with the coded arrangement of the windings. The depression of the key pulls a magnetic armature away from the upper magnetized stop member and towards the magnetic core element. The rapid movement of the armature which is provided by this "snap-action" assures that the rate of change of flux in the magnetic core will be sufficient to generate electrical output signals of a satisfactory magnitude. The upper stop member and its mounting structure provide a shunt path through which the magnetic flux in the armature by-passes the core when the key is in its rest position so as to minimize the flux flowing through the core until the key is depressed. A return spring and other means are described to return the armature to its original rest position after the key has been released by the operator. |
