Xerox Corporation

Carl E Herendeen

Robert A Ragen

John C Fravel

Louis H Chang

Frank D Ruble

Apparatus is disclosed for controlling the movement of a movable element between an initial starting position and a final stopping position. The apparatus comprises drive means coupled to the movable element and responsive to motor drive signals for moving the movable element along a predefined path between the starting and stopping positions; first benerating means coupled to the drive means for generating an actual velocity signal indicative of the actual speed of movement of the movable element; second generating responsive to a position signal indicative of the distance remaining to travel by the movable element toward the desired stopping position for generating first and second command velocity signals respectively indicative of the minimum and maximum desired velocity levels for such particular distance remaining to travel; and control means coupled to the first and second generating means and responsive to the position signal for comparing the actual velocity signal with each of the first and second command velocity signals when the value of the position signal indicates the movable element has greater than a predetermined distance to travel, and for issuing the motor drive signals in response to such comparison for application to the drive means to cause (a) the acceleration of the movable element by the drive means when the comparison indicates the actual velocity of the movable element is less than the minimum desired velocity, (b) the coasting of the movable element when the comparison indicates the actual velocity of the movable element is more than the minimum desired velocity and less than the maximum desired velocity, and (c) the deceleration of the movable element by the drive means when the comparison indicates the actual velocity of the movable element exceeds the maximum desired velocity.

Motion control apparatus

A serial printer comprises a carriage, a print member rotatably mounted to the carriage and including a plurality of character elements, a first drive coupled to the print member for rotating the print member to a desired rotational position in order to place a selected character element at a printing position adjacent a record medium to be printed upon, a second drive coupled to the carriage for moving the carriage along a predetermined path whereby the print member is caused to move to a desired printing position along the path, a first servo control coupled to the first drive means and responsive to a first set of input data and instructions for controlling the direction and speed of rotation of the print member, second servo control means coupled to the second drive and responsive to a second set of input data and instructions for controlling the direction and speed of movement of the carriage, and a programmed data processor coupled to the first and second servo control system for supplying at least some of the first set of input data and instructions under program control to the first servo control system and at least some of the second set of data and instructions to the second servo control system.

Control apparatus for serial printer

Apparatus for energizing a selected one or more of a plurality of actuation devices in order to cause a printing element associated with each selected actuation device to strike an adjacent recording medium. The apparatus comprises memory means responsive to a predetermined address signal for supplying a plurality of data bits and a conversion bit together identifying those actuation devices selected for energization, a plurality of switches respectively coupled to the plurality of actuation devices, each switch capable of energizing its respective actuation device in response to receipt of a data bit of a first state, means coupled to the memory means and to first and second predetermined ones of the switches and being responsive to the conversion bit being of a first state for supplying a predetermined data bit to the first predetermined switch and responsive to the conversion bit being of a second state for supplying the predetermined data bit to the second predetermined switch, and means coupled to the memory means and to other ones of the switches for respectively supplying other ones of the data bits to such other ones of the switches.

Growing community of inventors

Danville, CA, United States of America

Carl E Herendeen