Apparatus and method for automatically aligning print heads

A method of automatically aligning a selected print head module with respect to first, second and third axes of movement and automatically aligning a reference print module about the third axis of movement to improve image quality in an ink jet printer, the selected and reference print head modules being stationary during printing operations, the method comprising the steps of:

• a) printing a test pattern on a receiving substrate by ejecting ink drops from the selected print head module and from the reference print head module onto the receiving substrate;
• b) analyzing the test pattern to determine whether the selected print head module requires repositioning with respect to the reference print head module;
• c) analyzing the test pattern to determine whether the reference print module requires repositioning about the third axis of movement;
• d) translating the selected print head module along the first axis of movement to align the selected print head module with the reference print head module, wherein the first axis of movement is in a direction perpendicular to the direction of print media travel;
• e) translating the selected print head module along the second axis of movement to align the selected print head module with the reference print head module, wherein the second axis of movement is in a direction parallel to the direction of print media travel;
• f) rotating the selected print head module about the third axis of movement to align the selected print head module with respect to the first axis of movement and the second axis of movement, wherein the third axis of movement is perpendicular to the first and second axes of movement;
• and
• g) rotating the reference print head about the third axis of movement to align the reference print head module with respect to the first axis of movement and the second axis of movement.

A method of automatically aligning a print head with respect to its angular position about a first axis of movement to improve image quality in an ink jet printer, the method comprising the steps of:

• a) printing a test pattern on a receiving substrate by ejecting a plurality of ink drops from the print head onto the receiving substrate;
• b) determining whether the plurality of ink drops are equidistant along a second axis of movement;
• c) calculating an amount and direction of rotation of the print head about the first axis of movement that causes the print head to print the test pattern with ink drops that are equidistant along the second axis of movement;
• and
• d) rotating the print head about the first axis of movement to align the print head with respect to its angular position about the first axis of movement, wherein the first axis of movement is perpendicular to an axis of movement in a direction perpendicular to the direction of print media travel and perpendicular to an axis of movement parallel to the direction of print media travel.

A mounting for supporting and aligning a print head module with respect to three axes of movement, the print head module operating to jet ink onto a receiving substrate, the mounting comprising:

• a base;
• at least one flexure extending from the base to the print head module;
• first means for positioning the print head module along a first axis of movement, wherein the first axis of movement is in a direction parallel to the direction of print media travel;
• and
• second means for positioning the print head module along a second axis of movement, wherein the second axis of movement is in a direction perpendicular to the direction of print media travel and for rotating the print head module about a third axis of movement, wherein the third axis of movement is perpendicular to the first axis of movement and the second axis of movement.

A mounting for supporting and aligning a print head module with respect to three axes of movement, the print head module operating to jet ink onto a receiving substrate, the mounting comprising:

• a base;
• at least one flexure extending from the base to the print head module;
• first means for positioning the print head module along a first axis of movement, wherein the first means for positioning comprises:
• a first camming surface engaging a first control surface connected to a print head module;
• and means for rotating the first camming surface to impart translational movement along the first axis of movement to the print head module;
• and
• second means for positioning the print head module along a second axis of movement, and about a third axis of movement, wherein the second means for positioning comprises:
• a second camming surface engaging a second control surface connected to a first end of the print head module;
• a third camming surface engaging a third control surface connected to a second end of the print head module substantially opposite to the first end;
• a means for rotating the second camming surface to impart to the print head module translational movement along the second axis of movement and rotational movement about the third axis of movement;
• and
• a means for rotating the third camming surface to impart to the print head module translational movement along the second axis of movement and rotational movement about the third axis of movement.