ELECTROGRAPHIC PRINTING SYSTEM WITH PLURAL STAGGERED ELECTRODE ROWS

• US 3,624,661 A
• Filed: 05/14/1969
• Issued: 11/30/1971
• Est. Priority Date: 05/14/1969
• Status: Expired due to Term

• Current Assignee: Michael S. Shebanow, Ronald F. Borelli
• Original Assignee: Michael S. Shebanow, Ronald F. Borelli
• Inventors: Borelli, Ronald F., Shebanow, Michael S.
• Primary Examiner(s): Konick, Bernard
• Assistant Examiner(s): Britton, Howard W.
• Application Number:
  US04/824,419
• Time in Patent Office: 930 Days
• Field of Search: 346/74ES
• US Class Current: 347/141
• CPC Class Codes: B41J 2/395 Structure of multi-stylus heads
• CPC Class Codes: G03G 15/325 using a stylus or a multi-styli array
• CPC Class Codes: G06K 15/14 by electrographic printing, e.g. xerography; by magnetographic printing G06K15/12 takes precedence
• CPC Class Codes: Y10S 101/37 Printing employing electrostatic force

Abstract

In an electrographic printing system, a multiple row electrode structure wherein successive rows are mutually spaced from each other, each row including mutually spaced electrodes, the electrodes of successive rows being positioned in a staggered manner with respect to each other. The system further comprises improved electrode drive circuitry, including a plurality of high-voltage drivers and a selection matrix wherein a plurality of passive elements are coupled to the drivers. A plurality of output lines couple the matrix to the electrodes so as to selectively apply a high voltage to the electrodes in order to produce a latent image on a dielectric medium. Toning means subsequently make the latent image visible.

Claims

1. A CHARACTER GENERATOR

2. An electrographic printing system as defined in claim 1 wherein the spacing between successive rows of electrodes is substantially equal to the width of each of said electrodes in a direction transverse to said rows.

3. A SELECTION MATRIX INCLUDING A FIRST PLURALITY OF PASSIVE ELEMENTS COUPLED TO THE OUTPUT OF EACH OF SAID FIRST GROUP OF HIGH-VOLTAGE DRIVERS, A SECOND PLURALITY OF PASSIVE ELEMENTS COUPLED TO THE OUTPUT OF EACH OF SAID SECOND GROUP OF HIGHVOLTAGE DRIVERS, EACH OF SAID ELEMENTS COUPLED TO ONE OF SAID FIRST GROUP OF DRIVERS BEING CONNECTED TO FORM A COMMON NODE WITH A SEPARATE ELEMENT COUPLED TO ONE OF SAID SECOND GROUP OF DRIVERS, AN OUTPUT LINE CONNECTING EACH OF SAID NODES TO ONE OF SAID ELECTRODES, EACH OF SAID OUTPUT LINES BEING SELECTIVELY ADAPTED TO APPLY A HIGH VOLTAGE TO ITS CORRESPONDING ELECTRODE IN DEPENDENCE UPON THE OUTPUT OF SAID CHARACTER GENERATOR.

4. An electrographic printing system as defined in claim 1 wherein each of said passive elements includes a diode connected between the output of said high-voltage driver and said common node, said common node being resistively coupled to a reference potential.

5. An electrographic printing system as defined in claim 1 wherein each of said high-voltage drivers has an input terminal and an output terminal and further includes a. a first transistor having base, emitter and collector electrodes, said emitter being tied to ground and said base being coupled to said input terminal;

and b. a second transistor having base, emitter and collector electrodes, said last-recited emitter being connecTed to the collector electrode of said first transistor, said last-recited base being coupled to a reference potential, and said last-recited collector being coupled to said output terminal.

6. The printing system of claim 1 wherein said steady-state potential means is a roller employed to feed said medium along the prescribed path.

7. The printing system of claim 1 wherein each of said electrodes terminates in a common surface and said common surface is convex.

8. The printing system of claim 1 wherein said steady-state potential means is biased at a voltage of less magnitude than said high voltage applied to said electrodes when energized and greater than the voltage applied to said electrodes when not energized.

9. An electrographic printing system as defined in claim 1 wherein said electrodes terminate in a common surface, each electrode defining a working surface within said common surface, said working surfaces being aligned with respective spaces between the electrodes of successive rows and being dimensioned to substantially fill said spaces.

10. An electrographic printing system as defined in claim 9 wherein each of said working surfaces has a square shape.

11. In an electrographic printing system of the kind wherein a recording medium is moved along a path to have latent images formed thereon by the application of a high potential across the medium and wherein a toner is subsequently applied to the medium to make the latent image visible, an electrode structure adjacent said path including, a plurality of mutually spaced rows of electrodes, successive electrodes within each row being spaced from each other, the electrodes of successive rows being positioned in a staggered manner with respect to each other, means for selectively energizing individually, and a simple steady-state potential means disposed adjacent the opposite side of said path and extending substantially for an entire electrode row width for imparting a continuous potential across the medium over the width of an electrode row, wherein said single steady-state potential means is effective to provide a continuous potential to the medium for each successive row of said plurality of rows. 12 The apparatus as defined in claim 11, and further including electrode drive circuitry adapted to selectively energize said electrodes by applying a high voltage thereto.

13. The printing system of claim 11 wherein said steady-state potential means is a roller employed to feed said medium along a prescribed path.

14. The apparatus as defined in claim 11 wherein said electrode structure consists of a pair of spaced rows of electrodes, each electrode of a row being aligned with the space defined between the electrodes of the other row and having substantially the same dimension in a direction along said rows.

15. The apparatus of claim 14 wherein each of said electrodes terminates in a square working surface lying within a common surface, the spacing between said rows and between adjacent electrodes within a row being substantially equal to the side of one said square working surfaces.

16. The apparatus of claim 15 wherein said common surface defines a plane.

17. The apparatus of claim 15 wherein said common surface is convex.