High speed pagewidth inkjet printer

Abstract

An inkjet printer with a pair of inkjet printheads, each having an array of nozzles for ejecting ink, each nozzle having a corresponding nozzle in the array of the other printhead; wherein, defective nozzles in both of the arrays are identified and the printheads are paired such that the corresponding nozzles in each of the arrays are not both defective.

1 . An inkjet printer for printing sheets of media, the printer comprising: 
 a pair of inkjet printheads, each having an array of nozzles for ejecting ink, each nozzle having a corresponding nozzle in the array of the other printhead; wherein,    defective nozzles in both of the arrays are identified and the printheads are paired such that the corresponding nozzles in each of the arrays are not both defective.    
   
   
       2 . An inkjet printer according to  claim 1  further comprising a transfer roller for receiving ink from the nozzles in each of the arrays, and transferring it to a sheet of the media.  
   
   
       3 . An inkjet printer according to  claim 2  further comprising a cleaning station for engaging the transfer roller after ink has been transferred to the sheet of media but prior to receiving ink from the array of nozzles, the cleaning station having first and second cleaning members, the first cleaning member having a porous member for engaging the transfer roller to remove ink and the second cleaning member having an elongate resilient member for engaging the transfer roller after the first cleaning member for removing residual ink.  
   
   
       4 . An inkjet printer according to  claim 3  further comprising drying equipment for aiding drying of a printed image on the sheet of media.  
   
   
       5 . An inkjet printer according to  claim 4  wherein the drying equipment for aiding drying of a printed image on the sheet of media comprises a feed path along which the web of print media containing the printed image is fed after printing of the image on the print media; 
 a drive means for driving the web along the feed path at a predetermined rate; and    opposed IR lamps mounted on either side of the feed path.    a drive means for driving the web along the feed path at a predetermined rate; and    opposed IR lamps mounted on either side of the feed path.    
   
   
       6 . An inkjet printer according to  claim 3  wherein the first cleaning member is an elongate sponge that contacts the transfer roller along its entire length, and the second cleaning member is an elongate elastomeric wiper.  
   
   
       7 . An inkjet printer according to  claim 1  wherein the defective nozzles identified in each array are recorded as a characterisation vector for each individual printhead respectively such that if one of the printheads in the pair of printhead is replaced, a replacement printhead is selected to have a compatible characterisation vector that will ensure that corresponding nozzles in the pair of printheads will not both be defective.  
   
   
       8 . An inkjet printer according to  claim 1  wherein the printheads are pagewidth printheads.