摘要 |
A ballistic print hammer assembly which includes a pivotally mounted print hammer driven by an electromagnetic actuator, characterized by low cost and ease of manufacture, high velocity and short dwell time. A rigid pivot upon which the hammer is mounted is simply secured to one side of a frame member. One end of the hammer is disposed in a slot of the armature of the electromagnetic actuator. The stator of the actuator is arranged to be inserted (by means of screw threads) from the other side of the frame member through an aperture so that the armature fits within the actuator stator cavity. An impression control spring is further disposed in a central cavity of the armature to continually produce a biasing force on the hammer which in the free-flight condition of the hammer is a decelerating force. |