Contact pressure adjustment method and image recording apparatus

A contact pressure adjustment method applied to an image recording apparatus that records an image on a sheet,

• the image recording apparatus comprising:
• an image recording portion;
• a drive roller configured to convey the sheet along a predetermined conveying path by coming in contact with the sheet on which an image is recorded by the image recording portion and applying a conveying force to the sheet;
• a driven roller arranged at a position facing the drive roller and configured to be driven and rotated in contact with the image recording surface of the sheet with a predetermined contact pressure;
• and
• a vibration detection portion configured to detect vibration generated in the sheet conveyed on the conveying path;
• the contact pressure adjustment method comprising:
• causing the image recording portion to record a predetermined test image on the sheet;
• causing the vibration detection portion to detect vibration generated in a test-image-recorded-sheet on which the test image is recorded while the test-image-recorded-sheet is being conveyed along the conveying path;
• and
• adjusting the contact pressure with respect to the image recording surface of the test-image-recorded-sheet in a case where a fluctuation width of the vibration detected by the vibration detection portion is outside a predetermined reference range.