CIRCUMFERENTIAL AND LATERAL WEB REGISTRATION CONTROL SYSTEM

• US 3,701,464 A
• Filed: 10/15/1970
• Issued: 10/31/1972
• Est. Priority Date: 10/15/1970
• Status: Expired due to Term

• Current Assignee: Harris Graphics Corp. (Manroland GOSS Web Systems International LLC)
• Original Assignee: James N. Crum
• Inventors: Crum, James N.
• Primary Examiner(s): Robert E. Pulfrey
• Assistant Examiner(s): Eugene H. Eickholt
• Application Number:
  US05/081,041
• Time in Patent Office: 747 Days
• Field of Search: 101/181,248 226/16,30,31,2,3
• US Class Current: 226/3
• CPC Class Codes: B41F 13/14 with means for displacing the cylinders
• CPC Class Codes: B41F 33/02 Arrangements of indicating devices, e.g. counters
• CPC Class Codes: B65H 23/1882 and controlling longitudinal register of web

Abstract

A control system for controlling registration in a multi-color web-fed printing press system senses register marks which are printed on the web. Any circumferential registration error which is detected by sensors that sense the register marks is translated into a count in a circumferential counter which is coupled to a circumferential motor control circuit. The circumferential motor control circuit drives a stepping motor which in turn drives appropriate gearing to correct for the circumferential misregistration of the web as directed by the count in the circumferential counter. The apparent lateral registration error is then measured in a similar manner and is stored as a count in a lateral counter which corrects for lateral misregistration through a stepping motor and appropriate gearing. The error previously determined in the circumferential register is employed to correct the apparent error in the lateral register so that it represents the true lateral registration error instead of the apparent lateral registration error.

Claims

1. In a machine for operating on stock moving through the machine including first adjusting means for making a first adjustment of said stock relative to the operation performed by said machine on said stock with respect to a first degree of freedom, second adjustment means for making a second adjustment of said stock relative to the operation of said machine on said stock with respect to a second degree of freedom, sensor means for sensing a first register mark on said stock which indicates the relationship of said stock to the operation of said machine performed thereon with respect to said first degree of freedom and for sensing a second register mark on said stock to indicate the relationship of the stock to the operation of the machine with respect to said second degree of freedom, changes in the relationship of said stock to the operation of said machine with respect to the second degree of freedom effecting a change in the sensed relationship of said first mark independently of a change in the relationship of the machine and stock with respect to said first degree of freedom, and means responsive to said sensor means for ascertaining errors in the adjustment of said first and second adjusting means and providing first and second error signals for use in correcting said first and second adjusting means in dependency on the sensing of said first and second marks including means responsive to the sensing of said second mark for compensating said first error signal for error introduced by changes with respect to said second degree of freedom.

2. In a machine as defined in claim 1 wherein said means responsive to said sensor means comprises means responsive to said first and second marks for providing first and second control signals having a time duration in accordance with the magnitudes of error to be corrected by said first and second adjusting means, respectively, and integrating means responsive to the time duration of said first control signal to provide an error indication for said first adjusting means and responsive to the time duration of said second signal to compensate the said error indication to derive said first error signal in dependency on said first and second marks.

3. In a machine as defined in claim 2 wherein said integrating means comprises a pulse counter and means for transmitting pulses to said counter during said first control signal to register an error therein in dependency on said first mark and means for transmitting pulses during said second control signal to establish a count for compensating the count which is established during said first signal.

4. In a machine as defined in claim 3 wherein said counter is incrementally pulsed during said first and second control signals to establish a compensated error count therein.

5. In a machine as defined in claim 2 wherein said means responsivE to said sensor means includes reference means providing reference signals for indicating the time said first and second marks are to be sensed when adjustment is proper, means for providing first and second pulse signals indicating the time difference between said reference pulse and said first and second marks and direction signals for indicating the lead-lag relationship of the marks and the reference pulses, and a counter for counting pulses in a direction depending upon said direction signals during the time duration of said first and second pulse signals to provide said first error signal.

6. In a machine as defined in claim 5 wherein said reference means comprises means for providing first and second reference signals to be compared respectively with said first and second registration marks and said means responsive to said marks for providing said first and second control signals comprises circuit means actuated to two conditions by one of said reference signals and the corresponding one of said marks.

7. In a machine according to claim 6 wherein said circuit means is actuated to first and second conditions to provide one of said first and second control signals in response to one of said registration signals and the corresponding reference signal and includes means for resetting said circuit means to a third condition for actuation to said first and second conditions in response to the other mark and corresponding reference signal to provide the other of said first and second signals.

8. In a machine according to claim 7 wherein said circuit means comprises first and second two-stage circuits, one of said circuits being set in response to the registration mark and the other of said circuits being set in response to the reference mark and said means for resetting said circuit comprising means for resetting said first and second two-stage circuits.

9. In a machine according to claim 8 wherein said circuit means responsive to said sensor means includes means responsive to the actuation of said first and second two-stage circuits to determine which of the circuits is first actuated to determine the lead-lag relationship of the reference mark and its corresponding registration mark.

10. In a machine according to claim 9 in which said means responsive to said sensor means comprises means for inhibiting the response of said circuit means to said sensor means except for a predetermined period in the operation of said machine in which a register mark is to be passing said sensor means.

11. A method of correcting a false error indicated by the sensing of a registration mark for indicating the location of machine operation on the work with respect to an adjustment in one direction when the position of the mark on the work varies with the position of the stock relative to the machine in a degree of freedom controlled by a second adjustment, the relationship of the stock to the machine in the degree of freedom controlled by the second adjustment being indicated by the position of a second registration mark, comprising the steps of sensing the registration marks as they pass a fixed location, comparing the registration marks with a reference to determine time intervals that the marks are late or early in passing the location to ascertain the error in the adjustment in accordance with the time interval and modifying the error derived in dependency on the first mark before making the adjustment as a function of the error derived in dependency on said second mark.

12. A method of registering images printed by a press onto sheet material comprising the steps of printing first and second register marks indicating the position of the image on the sheet material transversely of and in the direction of movement of the sheet material through the press, the first mark being inclined relative to the line of movement of the sheet material through the press and the second mark being transverse to the line of movement, sensing the marks at a fixed location to determine thE time that the marks pass the location with respect to a reference to determine registration errors transversely of and in the direction of sheet movement and electrically combining the error sensed in the adjustment transversely of and in the direction of the movement of the the sheet to provide a corrected transverse error signal when errors are introduced into the error signal because of misregistration in the direction of sheet movement.

13. A method as defined in claim 12 in which a signal is derived from each of said registration marks as it passes said sensing means and is compared with reference signals for each mark indicating the time that the registration marks should be at the sensing means, the error in time being measured by pulsing a counter for registering the error in the direction transversely of the sheet movement both during the time interval between the arrive of the first and second registration marks at the sensing means and their respective reference signals.

14. In a printing press for printing an image on sheet stock moving through the machine including first adjusting means for making a first adjustment of said stock relative to the printing operation performed by said machine on said stock, second adjustment means for making a second adjustment of said stock relative to the printing operation of said machine on said stock, sensor means for sensing a first register mark on said stock which indicates the relationship of the printed image on said stock with respect to a first degree of freedom controlled by said first adjustment and for sensing a second register mark on said machine to indicate the relationship of the printed image on said stock with respect to a second degree of freedom controlled by said second adjustment means, changes in the position of the image on said stock with respect to the second degree of freedom effecting a change in the sensed relationship derived from said first mark independently of a change in the relationship of the image on the stock with respect to said first degree of freedom, means responsive to said sensor means for ascertaining errors in the adjustment of said first and second adjusting means and providing first and second error signals for correcting said first and second adjusting means including means responsive to the sensing of said second mark for compensating said first error signal for false errors introduced by errors in said second adjusting means.

15. In a method of operating a machine in which a cyclical work operation is performed on stock moving in one direction through a machine with the work operation being controlled with respect to a first degree of freedom, applying first register marks to said stock whose times of arrival at a sensing station as compared to a reference indicate the adjustment of the machine with respect to a first degree of freedom, the times of arrival of said first register marks at said first station varying in accordance with the adjustment of the machine with respect to a second degree of freedom, applying register marks said stock whose time of arrival at said station with respect to a reference indicates the adjustment of said machine with respect to said second degree of freedom, and sensing the times of arrival of said first and second marks at said station to provide error signals for controlling the adjustment of the machine with respect to said first degree of freedom including compensating the error signal derived in dependency on the arrival of said first register marks in accordance with the time of arrival of said second register marks at said station to render the error signal for adjusting the machine with respect to said first degree of freedom independent of the adjustment of said machine with respect to said second degree of freedom.

16. In a method as defined in claim 15 wherein said first degree of freedom is transversely of the line of movement of the stock through the machine and the first register mark comprises a line which is inclined with respect to the line of movement.

17. In a method as defined in claim 16 wherein said second degree of freedom is along the line of movement of the said material through the machine.