Method of adjusting image recording apparatus for correcting skew

• US 7,548,326 B2
• Filed: 03/21/2005
• Issued: 06/16/2009
• Est. Priority Date: 03/22/2004
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Fukushima, Kimitake
• Primary Examiner(s): Poon; King Y
• Assistant Examiner(s): Cammack; David S
• Application Number:
  US11/085,017
• Publication Number:
  US 20050207740A1
• Time in Patent Office: 1,548 Days
• Field of Search: 358/1.12, 400/579, 382/294
• US Class Current: 358/1.12
• CPC Class Codes: H04N 1/00002 Diagnosis, testing or measuring; Detecting, analysing or monitoring not otherwise provided for error detection, error correction or monitoring in digital computers or digital computer components G06F11/00
• CPC Class Codes: H04N 1/00015 Reproducing apparatus
• CPC Class Codes: H04N 1/00031 Testing, i.e. determining the result of a trial H04N1/00029 takes precedence; using test signals for transmission mode changing H04N2201/33371
• CPC Class Codes: H04N 1/00045 using a reference pattern designed for the purpose, e.g. a test chart
• CPC Class Codes: H04N 1/0005 in service, i.e. during normal operation
• CPC Class Codes: H04N 1/00063 using at least a part of the apparatus itself, e.g. self-testing
• CPC Class Codes: H04N 1/00068 Calculating or estimating
• CPC Class Codes: H04N 1/00076 locally
• CPC Class Codes: H04N 1/00087 Setting or calibrating picture signal circuits H04N1/40
• CPC Class Codes: H04N 1/0009 Storage
• CPC Class Codes: H04N 1/047 Detection, control or error compensation of scanning velocity or position H04N1/0402 and H04N1/17 take precedence
• CPC Class Codes: H04N 1/3878 Skew detection or correction
• CPC Class Codes: H04N 2201/04756 by controlling the position or movement of the sheet, the sheet support or the photoconductive surface
• CPC Class Codes: H04N 2201/04758 by controlling the position of the scanned image area H04N2201/04755, H04N2201/04756 take precedence
• CPC Class Codes: H04N 2201/04789 in the main-scan direction
• CPC Class Codes: H04N 2201/04791 in the sub-scan direction

Abstract

A printer processor prints out two sheets of test prints by printing a test pattern on two recording sheets of different lengths. The test pattern consists of eight straight-linear lines that are parallel to a main scan direction or a sub scan direction of an exposure section. Dimensions of designated portions of the test pattern are measured on each of the test prints, to detect skew characteristics of the recording sheets, deviations of print starting positions in the main and sub scan directions and fluctuations in transport speed of the recording sheets. Based on the detected values, a skew correcting section, the exposure section and a conveyer device for the recording sheets are controlled to correct skew of the recording sheets, the print starting positions in the main and sub scan directions and the transport speed.

Claims

1. A method of adjusting an image recording apparatus that comprises a recording material supply section for supplying sheets of recording material, a conveyer device for conveying the recording material along a transport path, a recording device for recording an image on the recording material as being conveyed, and a skew correction device for correcting skew of the recording material on said transport path so as to make a leading edge of each sheet of the recording material be parallel to a main scan direction that is a widthwise direction of said transport path, said method comprising steps of:

supplying first and second sheets of recording material from said recording material supplying section, said first and second sheets being different in length in a sub scan direction that is a lengthwise direction of said transport path;

recording a test pattern on said first and second sheets of recording material by said recording device, to produce first and second test prints, said test pattern having a first line that is defined to be parallel to said sub scan direction;

measuring distances from one side of each of said test prints to two different points of said first line as recorded on each of said test prints;

calculating a skew degree of each of said first and second test prints from said measured two distances;

calculating skew characteristics of each of said first and second sheets of recording material from said skew degrees of said first and second test prints, said skew characteristics being dependent upon a location of said recording material supply section and the lengths in the sub scan direction of said first and second sheets; and

adjusting, based on the calculated skew characteristics, correction parameters for said skew correction device to correct skew of recording materials supplied from said recording material supply section;

wherein said test pattern comprises a plural number of second lines defined to be parallel to the main scan direction, and a third line that is symmetrical to said first line about a referential line connecting center points of said second lines to each other, and said method further comprises steps of;

calculating a variation of a print starting position in the main scan direction based on a difference between a distance from the one side edge to said first line and a distance from opposite side edge to said third line with respect to either of said test prints; and

adjusting the print starting position in the main scan direction by controlling said recording device based on the calculated variation of the print starting position in the main scan direction.

2. A method of adjusting an image recording apparatus as claimed in claim 1, wherein said image recording apparatus comprises a second recording material supply section, and said method further comprises steps of:

supplying a third sheet of recording material from said second recording material supplying section, said third sheet being equal in length in the sub scan direction to said first sheet;

recording a test pattern on said third sheet, to produce a third test print;

measuring distances from one side of said third test print to two different points of said first line as recorded on said third test print;

calculating a skew degree of said third test print from said measured two distances;

calculating skew characteristics of said third sheet of recording material from said skew degrees of said first and third test prints, said skew characteristics being dependent upon a location of said second recording material supply section and the length in the sub scan direction of said third sheet; and

adjusting, based on the calculated skew characteristics of said third sheet, correction parameters for said skew correction device to correct skew of recording materials as supplied from said second recording material supply section.

3. A method of adjusting an image recording apparatus as claimed in claim 1, wherein said test pattern comprises a second line that is defined to be parallel to said main scan direction, and said method further comprises steps of:

calculating a variation of a print starting position in the sub scan direction based on a distance from a leading end to said second line of either of said test prints; and

adjusting the print starting position in the sub scan direction by controlling said recording device based on the calculated variation of the print starting position in the sub scan direction.

4. A method of adjusting an image recording apparatus as claimed in claim 3, wherein said recording material supply section is loaded with one of different kinds of exchangeable recording material containers, and a test print is made to adjust the correction parameters for said skew correction device and the print starting position in the sub scan direction with respect to each of said recording material containers.

5. A method of adjusting an image recording apparatus as claimed in claim 1, wherein said recording material supply section is loaded with one of different kinds of exchangeable recording material containers, and a test print is made to adjust the correction parameters for said skew correction device and the print starting position in the main scan direction with respect to each of said recording material containers.

6. A method of adjusting an image recording apparatus as claimed in claim 1, wherein said test pattern comprises at least two second lines defined to be parallel to the main scan direction and spaced apart from each other at a predetermined distance, and said method further comprises steps of measuring a distance between said second lines on either of said test prints to calculate a fluctuation in transport speed of the recording material, and controlling said conveyer device to adjust the transport speed based on the calculated fluctuation in transport speed.

7. A method of adjusting an image recording apparatus as claimed in claim 6, wherein said recording material supply section is loaded with one of different kinds of exchangeable recording material containers, and said method further comprises steps of making a test print on each of recording materials of different widths supplied from different ones of said recording material containers, calculating fluctuation characteristics of the transport speed to the width or length in the main scan direction of each of said recording materials, to adjust the transport speed with respect to each of said recording material containers.

8. A method of adjusting an image recording apparatus as claimed in claim 1, further comprising a step of providing information identifying said test prints on a front side or a back side of each of said test prints.

9. A method of adjusting an image recording apparatus that comprises a recording material supply section for supplying sheets of recording material, a conveyer device for conveying the recording material along a transport path, a recording device for recording an image on the recording material as being conveyed, and a skew correction device for correcting skew of the recording material on said transport path so as to make a leading edge of each sheet of the recording material be parallel to a main scan direction that is a widthwise direction of said transport path, said method comprising steps of:

supplying first and second sheets of recording material from said recording material supplying section, said first and second sheets being different in length in a sub scan direction that is a lengthwise direction of said transport path;

recording a test pattern on said first and second sheets of recording material by said recording device, to produce first and second test prints, said test pattern having a first line that is defined to be parallel to said sub scan direction;

measuring distances from one side of each of said test prints to two different points of said first line as recorded on each of said test prints;

calculating a skew degree of each of said first and second test prints from said measured two distances;

calculating skew characteristics of each of said first and second sheets of recording material from said skew degrees of said first and second test prints, said skew characteristics being dependent upon a location of said recording material supply section and the lengths in the sub scan direction of said first and second sheets; and

adjusting, based on the calculated skew characteristics, correction parameters for said skew correction device to correct skew of recording materials supplied from said recording material supply section

wherein said image recording apparatus comprises a second recording material supply section, said test pattern comprises a second line that is defined to be parallel to said main scan direction, a plural number of second lines defined to be parallel to the main scan direction, and a third line that is symmetrical to said first line about a referential line connecting center points of said second lines to each other, and said method further comprises steps of;

supplying a third sheet of recording material from said second recording material supplying section, said third sheet being equal in length in the sub scan direction to said first sheet;

recording a test pattern on said third sheet, to produce a third test print;

measuring distances from one side of said third test print to two different points of said first line as recorded on said third test print;

calculating a skew degree of said third test print from said measured two distances;

calculating skew characteristics of said third sheet of recording material from said skew degrees of said first and third test prints, said skew characteristics being dependent upon a location of said second recording material supply section and the length in the sub scan direction of said third sheet;

adjusting, based on the calculated skew characteristics of said third sheet, correction parameters for said skew correction device to correct skew of recording materials as supplied from said second recording material supply section;

calculating a variation of a print starting position in the sub scan direction based on a distance from a leading end to said second line of either of said test prints;

calculating a variation of a print starting position in the main scan direction based on a difference between a distance from the one side edge to said first line and a distance from opposite side edge to said third line with respect to each of said first and third test prints;

adjusting the print starting positions in the main and sub scan directions by controlling said recording device based on the calculated variations of the print starting positions in the main and sub scan directions.

10. A method of adjusting an image recording apparatus as claimed in claim 9, wherein said first and third sheets of recording material have different widths, and said method further comprises steps of measuring a distance between said second lines on either of said test prints to calculate a fluctuation in transport speed of the recording material, and calculating fluctuation characteristics of the transport speed to the width or length in the main scan direction of each of said recording materials, to adjust the transport speed with respect to each of said recording material containers controlling said conveyer device to adjust the transport speed based on the calculated transport speed.

11. A method of adjusting an image recording apparatus as claimed in claim 10, wherein said recording material supply section is loaded with one of different kinds of exchangeable recording material containers, and said method further comprises steps of making a test print with respect to each of said recording material containers, to adjust the correction parameters for said skew correction device, the print starting positions in the main and sub scan directions and the transport speed of said conveyer device individually on each of said recording material containers.

12. A method of adjusting an image recording apparatus as claimed in claim 11, wherein said image recording apparatus comprises a display device, and said method comprises steps of displaying a selected one of setting screens on said display device, said setting screens comprising one for allowing adjusting the correction parameters for said skew correction device, the transport speed of said conveyer device and the print starting positions in the main and sub scan directions simultaneously with respect to all of said recording material containers, and ones for allowing adjusting any of the correction parameters for said skew correction device, the transport speed of said conveyer device, the print starting position in the main scan direction or the print starting position in the sub scan direction with respect to individual one of said recording material containers.