Method and system for controlling multicolor ink-jet printing on intermittent rotary printing device

1. A control method for a digital ink-jet printing device to carry out multicolor ink-jet printing on an intermittent rotary printing device, the digital ink-jet printing device including a plurality of imaging component groups, said control method performs the following control operations for each of the imaging component groups, respectively:

determining whether a current page to be printed is the first page of a job to be printed;

if the current page is the first page, calculating a length of an image to be printed on the current page by subtracting a distance between the imaging component group and a reference from a length of an image of a page of the job, wherein the reference is the foremost printing imaging component group in a movement direction of a printed body, acquiring image data of the current page, the length of which is the calculated length, from a data storage space storing image data of the job after delaying the distance, and sending the acquired data to the digital ink-jet printing device to carry out the printing;

if the current page is not the first page, acquiring unprinted image data of a previous page, the length of which is the distance, and image data of the current page, the length of which is the calculated length, from the data storage space, and sending the acquired data to the digital ink-jet printing device to carry out the printing; and

determining whether the current page is the last page of the job, and if the current page is not the last page of the job, repeating the steps mentioned above.

2. The control method of the claim 1 , wherein, the control operations further includes:

in the printing process, comparing the length of the printed image with the calculated length to determine whether the current page has been printed completely.

3. The control method of the claim 1 , wherein, as for the foremost printing imaging component group in the movement direction of the printed body, the distance is zero (0).

4. The control method of the claim 1 , wherein, image data to be printed by each imaging component group is separately stored in different data storage space.

5. A control system for a digital ink-jet printing device to carry out multicolor ink-jet printing on an intermittent rotary printing device, the digital ink-jet printing device including a plurality of imaging component groups, said control system including a plurality of control devices for controlling each of imaging component groups respectively, and each of the control devices comprises:

a register stack for storing a length of an image of a page of a job to be printed and a distance between an imaging component group controlled by the control device and a reference, wherein the reference is the foremost printing imaging component group in a movement direction of a printed body;

a determining unit for determining whether a current page to be printed is the first page;

a selecting switch for selecting the distance when the determining unit determines that the current page is the first page, and selecting zero (0) when the determining unit determines that the current page is not the first page;

a subtracter for subtracting the selection result of the selecting switch from the length of the image stored in the register stack to obtain a length of an image to be printed on the current page;

a counter for counting delays in the following manner: starting from an initial value corresponding to the selection result of the selecting switch, a counter value is decreased by one (1) every time a unit distance is delayed until the counter value becomes zero (0); and

a data reading unit for acquiring image data of the current page to be printed from a data storage space storing image data of the job in the following manner when the counter value becomes zero (0) and sending the acquired data to the digital ink-jet printing device to carry out the printing: when the determining unit determines that the current page is the first page, acquiring the image data of the current page, the length of which is a value of the subtracter; when the determining unit determines that the current page is not the first page, acquiring unprinted image data of a previous page, the length of which is the distance stored in the register stack and the image data of the current page, the length of which is a value obtained by subtracting the distance from the value of the subtracter.

6. The control system of the claim 5 , wherein, the control device further includes:

an adder for calculating a length of the printed image in the following manner: a value of the adder is increased by one (1) every time data of a unit distance is printed; and

a comparator for comparing the value of the adder with the value of the subtracter so as to determine whether the current page is printed completely.

7. The control system of the claim 5 , wherein, as for the foremost printing imaging component group in the movement direction of the printed body, the distance is zero (0).

8. The control system of the claim 5 , wherein, image data to be printed by each imaging component group is separately stored in different data storage space.

9. The control system of the claim 5 , wherein, the determining unit includes a second counter and a second comparator, wherein the second counter counts the number of printed pages and an initial value of the second counter is zero (0); the second comparator compares a value of the second counter with one (1), and if the value of the second counter is less than one (1), it is determined that the current page is the first page, otherwise it is determined that the current page is not the first page.