Printing apparatus employing stepping motor control system

Claim 2

Apparatus for recording latent electrostatic images in the form of alphanumeric characters in spaces on an insulating recording medium comprising a carrier member having a stylus formed thereon, said stylus comprising a plurality of electrical conductors, a guide member having a slot along a portion of its surface for receiving said carrier member and holding said stylus in spatial relation to said recording medium, said carrier member having freedom of linear movement within said slot, a bi-directional stepping motor coupled to said carrier member for moving said carrier member within said slot, means responsive to input signals representing said alphanumeric characters for energizing said stepping motor to move said carrier member between a first and a second position in discrete predetermined steps, and character generating means responsive to said input signals for applying electrical signals to said electrical conductors to record said latent electrostatic images on said recording medium.

Claim 3

The apparatus as defined in claim 1 wherein said discrete step of said stepping motor causes said carrier member to move across said recording medium a single one of said spaces, said apparatus further including encoder means coupled to said stepping motor for providing signals which represent divisions of the discrete step, said character generating means being responsive to said encoder means signals for recording characters within said spaces.

Claim 4

The apparatus as defined in claim 1 wherein said carrier member comprises a flexible strip of material having a connector at one end thereof for connection to said character generating means, said apparatus further including loop forming means for directing said carrier member to form a loop as said carrier member exits from said guide member.

Claim 5

Printing apparatus comprising an insulated recording medium, a carrier member, a stylus comprising a columnar array of electrical conductors mounted on said carrier member, guide means for retaining said carrier member and holding said stylus a fixed distance from said recording medium, said guide means including means for allowing said stylus to move in a linear fashion between a first position and a second position, a bi-directional stepping motor coupled to said carrier member for moving said carrier member in said guide means, control means responsive to a signal representing an alphanumeric character for controlling said stepping motor to move said stylus on said carrier member a predetermined distance from said first position toward said second position, and means responsive to said alphanumeric character signal for applying electrical pulses to the conductors of said stylus so as to form an electrostatic image of said alphanumeric character on said recording medium in the space defined by said predetermined distance.

Claim 6

Printing apparatus comprising an insulated recording medium, a carrier member, a stylus comprising a columnar array of electrical conductors mounted on said carrier member, guide means for retaining said carrier member and holding said stylus a fixed distance from said recording medium, said guide means including means for allowing said stylus to move in a linear fashion between a first position and a second position, a bi-directional stepping motor coupled to said carrier member for moving said carrier member in said guide means, control means responsive to a signal representing an alphanumeric character for controlling said stepping motor to move said stylus on said carrier member a predetermined distance from said first position toward said second position, and means responsive to said alphanumeric character signal for applying electrical pulses to the conductors of said stylus so as to form an electrostatic image of said alphanumeric character on said recording medium in the space defined by said predetermined distance.

Claim 7

The apparatus of claim 4 wherein said control means comprises means responsive to said stylus reaching said second position for activating said stepping motor to return s aid stylus to said first position.

Claim 8

The apparatus of claim 5 wherein said carrier member comprises a flexible strip of material, said apparatus further including loop forming means for directing said carrier member to form a loop as said carrier member exits from said guide means when said stylus is moved from said first position toward said second position.

Claim 9

The apparatus of claim 5 wherein said control means comprises first means coNtrollable for generating either a first or a second set of signals, second means controllable for generating either said first or said second set of signals, means for applying the signals generated by said first means and said second means to said stepping motor, and direction control means for controlling said first means to generate said first set of signals and said second means to generate said second set of signals whereby said stepping motor is driven in a first direction and for controlling said first means to generate said second set of signals and said second means to generate said first set of signals whereby said stepping motor is driven in a second direction.

Claim 10

The system of claim 7 wherein said applying means includes speed control means for varying the magnitude of the signals applied to said stepping motor whereby the speed of said stepping motor may be controlled.

Claim 11

The system of claim 8 wherein said speed control means includes a plurality of amplifiers and means for activating selected ones of said amplifiers to provide incremental motor speed variations.