# US 7,607,752 B2 · Misfiring print nozzle compensation

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 7,607,752 B2
- Document ID: US7607752B2
- Status: Granted
- Kind: B2
- Application number: 11/601,312
- Filed: 2006-11-17
- Published: 2008-05-22
- Granted: 2009-10-27
- Earliest claimed: 2006-11-17
- Assignees: Hewlett-Packard Development Company, L.P.
- Inventors: Winthrop D. Childers; Ronald A. Askeland; Guo Li
- Web page: https://patentgrep.com/patent/US7607752B2

## CPC

- B41J 29/393: Devices for controlling or analysing the entire machine {; Controlling or analysing mechanical parameters involving printing of test patterns}
- B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS

## Abstract

Embodiments including misfiring print nozzle compensation are disclosed.

## Claims

### Claim 1

A method for misfiring print nozzle compensation, comprising:
generating a test pattern on a print medium using a number of print nozzles arranged into a plurality of columnar groups of nozzles in a printhead module of an imaging device before initiating a print job;
examining the test pattern to determine whether one or more among the number of print nozzles is misfiring;
identifying which of the number of print nozzles is capable of addressing one or more locations indicating misfiring of one or more print nozzles; and
compensating at least partially for the one or more misfiring print nozzles by repositioning of one or more of the columnar groups of nozzles including one or more print nozzles capable of substituting for the identified one or more misfiring print nozzles in another of the columnar groups of nozzles at the one or more addressed locations on the print medium.

### Claim 2 (depends on 1)

The method of claim 1, further comprising using a web press printer for printing on a continuous sheet of print medium with one or more of the columnar groups of nozzles each including inkjet print nozzles.

### Claim 3 (depends on 2)

The method of claim 2, wherein a positioning of the one or more of the columnar groups of nozzles is performed by arraying each of the columnar groups of nozzles substantially transverse relative to a progression of the print medium.

### Claim 4 (depends on 3)

The method of claim 3, wherein the positioning of the columnar groups of nozzles is performed by grouping columnar groups of nozzles using a same colorant together in one or more modules when more than one columnar groups of nozzles is utilized.

### Claim 5 (depends on 4)

The method of claim 4, wherein the positioning of the more than one columnar groups of nozzles in the module involves staggering the positions of the print nozzles of a first columnar groups of nozzles relative to the print nozzles of a second columnar groups of nozzles, wherein the staggering is substantially arrayed transverse relative to the progression of the print medium.

### Claim 6 (depends on 1)

The method of claim 1, wherein repositioning of the one or more print nozzles carried by the one or more columnar groups of nozzles is performed by repositioning of the one or more columnar groups of nozzles substantially transverse relative to a progression of the print medium.

### Claim 7 (depends on 6)

The method of claim 6, wherein repositioning of the one or more columnar groups of nozzles substantially transverse results in enabling one or more print nozzles to substitute for the one or more misfiring print nozzles at the one or more addressed locations on the print medium.

### Claim 8

A method of compensating for misfiring of a print nozzle, comprising:
generating a test pattern on a print medium using a number of print nozzles arranged as a plurality of columns in a printhead module of an imaging device before initiating a print job;
identifying which of the number of print nozzles can address defined locations on the print medium;
analyzing a print job prior to printing to identify which among the number of print nozzles will supply a first colorant to one or more defined locations in forming an image on the print medium; and
selecting one or more print nozzles in another of the plurality of columns of nozzles capable of supplying at least a second colorant to the one or more defined locations on the print medium to which the first colorant is intended to be supplied.

### Claim 9 (depends on 8)

The method of claim 8, further comprising using a web press printer for printing on a continuous sheet of print medium with one or more of the columnar groups of nozzles inkjet print nozzles.

### Claim 10 (depends on 8)

The method of claim 8, further comprising printing of the image on the print medium by underprinting with at least the second colorant using the one or more selected print nozzles at each of the one or more defined locations to which the first colorant is intended to be supplied.

### Claim 11 (depends on 10)

The method of claim 10, wherein underprinting with at least the second colorant results in at least partially compensating for misfiring of one or more print nozzles intended to supply the first colorant at each of the one or more defined locations.

### Claim 12

A printing system, comprising:
a commercial web press printer for printing on a continuous sheet of print medium with a plurality of columnar groups of inkjet print nozzles; and
computer executable instructions stored in a memory and executable by a processor to at least partially compensate for one or more misfiring print nozzles, wherein the computer executable instructions are executed to:
generate a test pattern on the print medium using a number of print nozzles of an imaging device before initiating a print job;
examine the test pattern to determine whether one or more among the number of print nozzles is misfiring;
identify which of the number of print nozzles is capable of addressing one or more locations indicating misfiring of one or more print nozzles; and
compensate at least partially for the one or more misfiring print nozzles by substituting firing of one or more print nozzles on another of the columnar groups of inkjet print nozzles for the identified one or more misfiring print nozzles at the one or more addressed locations to print on the print medium using the web press printer.

### Claim 13 (depends on 12)

The system of claim 12, wherein the computer executable instructions are executed to substitute firing of one or more print nozzles using a colorant that is the same as the colorant used in the one or more misfiring print nozzles.

### Claim 14 (depends on 13)

The system of claim 13, wherein the computer executable instructions are executed to substitute firing of one or more print nozzles using one or more colorants that are different from the colorant used in the one or more misfiring print nozzles when one or more print nozzles firing the same colorant is not available.

### Claim 15 (depends on 14)

The system of claim 14, wherein the computer executable instructions are executed to determine which of a number of colorants utilized in the print nozzles can be used to substitute for the one or more misfiring print nozzles when substituting firing of one or more print nozzles using a colorant that is different.

### Claim 16 (depends on 15)

The system of claim 15, wherein the computer executable instructions are executed to substitute firing of one or more print nozzles having a white ink colorant when the one or more misfiring print nozzles have a yellow colorant and when one or more print nozzles firing the same colorant is not available.

### Claim 17 (depends on 15)

The system of claim 15, wherein the computer executable instructions are executed to substitute firing of one or more print nozzles having a cyan ink colorant when the one or more misfiring print nozzles have a black colorant and when one or more print nozzles firing the same colorant is not available.

### Claim 18 (depends on 15)

The system of claim 15, wherein the computer executable instructions are executed to substitute firing of one or more print nozzles having a black ink colorant when the one or more misfiring print nozzles have a magenta colorant and when one or more print nozzles firing the same colorant is not available.

### Claim 19 (depends on 18)

The system of claim 18, wherein the computer executable instructions are executed to adjust color in a region in which one or more print nozzles are used for substituting one or more colorants that are different from the colorant used in the one or more misfiring print nozzles.

### Claim 20 (depends on 19)

The system of claim 19, wherein the computer executable instructions are executed to register a repositioning of the one or more print nozzles and to initiate a print job using the repositioned one or more print nozzles to compensate at least partially for the one or more misfiring print nozzles.