Page Wide Array Printer Nozzle Uniformity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional page-wide array (PWA) printers experience non-uniform nozzle ageing due to uneven usage, leading to reduced image quality and premature nozzle failure, as certain nozzles are used more frequently than others, especially when printing standardized elements like borders and titles, resulting in defects such as coloration issues and the need for early print bar replacement.

Innovation Solution

The PWA printer incorporates a print bar transport mechanism that allows for lateral movement of the print bar between or within print jobs, enabling more uniform nozzle usage by reconfiguring the nozzles and adjusting their alignment relative to the substrate, ensuring even ageing and extending nozzle life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the print bar is fixed and the substrate is moved for printing, then the printing process is simple and fast, but the nozzles experience non-uniform usage leading to uneven ageing and reduced reliability

Engineering Contradiction:
Improvenozzle usage uniformityVSAvoidprinter structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies the dynamics principle by transforming the fixed print bar into a movable one. The print bar is now capable of lateral movement along the substrate width, allowing different nozzle subsets to be positioned over the substrate during different print jobs. This dynamic repositioning ensures uniform nozzle usage across all nozzles, preventing uneven ageing and improving reliability without significantly complicating the overall printer structure.

Inventive Principle:
Principle #15Dynamics

2Productivity

If certain nozzles are used more frequently due to standardized print elements, then the printing process is efficient, but the frequently used nozzles age prematurely causing image quality degradation

Engineering Contradiction:
Improveprinting efficiencyVSAvoidnozzle service life
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The movable print bar enables dynamic redistribution of printing tasks across different nozzle subsets. By laterally repositioning the print bar between print jobs, nozzles that would otherwise be overused due to standardized print elements are given rest periods, while previously underutilized nozzles are activated. This dynamic load balancing maintains high printing efficiency while extending the service life of individual nozzles.

Inventive Principle:
Principle #15Dynamics

3Reliability

If the print bar remains stationary, then the alignment and positioning are simple, but the nozzles at the ends remain idle causing coloration defects

Engineering Contradiction:
Improveprinting quality uniformityVSAvoidprint bar mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements lateral movement of the print bar to activate end nozzles that would otherwise remain idle. By repositioning the print bar to different lateral positions during operation, all nozzles including those at the ends are utilized for printing. This eliminates the idle time of end nozzles and prevents the coloration defects that arise from non-uniform usage, while keeping the mechanical complexity manageable through a straightforward translation mechanism.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2981415B1Page wide array printer
Publication Date: 2019.10.09 HEWLETT PACKARD DEVELOPMENT COMPANY LP
  • EP2981415B1 patent drawingFigure 1~2
  • EP2981415B1 patent drawingFigure 3
  • EP2981415B1 patent drawingFigure 4A~4C

AI summary

The present disclosure discloses a page wide array (PWA) printer (20) particularly but not exclusively for performing print jobs while maximizing print bar performance uniformity within the printer. The PWA printer includes a print bar which can be moved laterally and a controller which causes the print bar to laterally move from a first to a second position and causes the nozzles within the print bar to print an image while the print bar is in the second position without modifying the lateral alignment of the image.