Modular system for detecting inoperative ejectors in three-dimensional object printers

A three-dimensional object printer comprising:

• a printhead including a plurality of ejectors configured to eject drops of a marking agent;
• at least one actuator operatively connected to the printhead, the at least one actuator being configured to move the printhead along a member;
• and
• a printhead maintenance module, the printhead maintenance module having:
• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• a heater mounted to the platen to heat media as the media passes over the heater;
• and
• a controller operatively connected to the printhead, the at least one actuator, each electric motor, the heater, and the optical sensor in the sensor assembly, the controller being configured to:
• operate the at least one actuator to move the printhead to a position opposite the platen in the frame;
• operate the plurality of ejectors in the printhead to eject drops of the marking agent onto media adjacent the platen to form a printed test pattern;
• operate one of the electric motors to rotate at least one of the rollers to move the media from the position opposite the printhead to a position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• identify inoperative ejectors with reference to the image data of the test pattern;
• and
• activate the heater selectively.

A three-dimensional object printer comprising:

• a printhead including a plurality of ejectors configured to eject drops of a marking agent;
• at least one actuator operatively connected to the printhead, the at least one actuator being configured to move the printhead along a member;
• and
• a printhead maintenance module, the printhead maintenance module having:
• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• and
• a controller operatively connected to the printhead, the at least one actuator, each electric motor, and the optical sensor in the sensor assembly, the controller being configured to:
• operate the at least one actuator to move the printhead to a position opposite the platen in the frame;
• operate the plurality of ejectors in the printhead to eject drops of the marking agent onto media adjacent the platen to form a printed test pattern;
• operate one of the electric motors to rotate at least one of the rollers to move the media from the position opposite the printhead to a position opposite the optical sensor in the sensor assembly;
• operate the other electric motor to move the media between the position where the test pattern is printed and the position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern.

A three-dimensional object printer comprising:

• a printhead including a plurality of ejectors configured to eject drops of a marking agent;
• at least one actuator operatively connected to the printhead, the at least one actuator being configured to move the printhead along a member;
• and
• a printhead maintenance module, the printhead maintenance module having:
• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence, wherein the at least two electrical motors are configured to rotate each of the rollers independently and bidirectionally;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• and
• a controller operatively connected to the printhead, the at least one actuator, each electric motor, and the optical sensor in the sensor assembly, the controller being configured to:
• operate the at least one actuator to move the printhead to a position opposite the platen in the frame;
• operate the plurality of ejectors in the printhead to eject drops of the marking agent onto media adjacent the platen to form a printed test pattern;
• operate one of the electric motors to rotate at least one of the rollers to move the media from the position opposite the printhead to a position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern.

A printhead maintenance module for a three-dimensional object printer comprising:

• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence to enable independent and bidirectional rotation of each roller;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• at least two pivoting arms to which the sensor assembly is mounted, the at least two pivoting arms being mounted to the frame about pivot pins to enable the pivoting arms to move between a position where the optical sensor generates image data of the printed test pattern on the media and a position where one of the rollers is accessible for removal;
• and
• a controller operatively connected to each electric motor and the optical sensor in the sensor assembly, the controller being configured to:
• operate one of the electric motors to rotate at least one of the rollers to move media from a position opposite a printhead where a test pattern is printed on the media to a position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern.

A printhead maintenance module for a three-dimensional object printer comprising:

• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence to enable independent and bidirectional rotation of each roller;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• a heater mounted to the platen to heat the media as the media passes over the heater;
• and
• a controller operatively connected to each electric motor, the heater, and the optical sensor in the sensor assembly, the controller being configured to:
• operate one of the electric motors to rotate at least one of the rollers to move media from a position opposite a printhead where a test pattern is printed on the media to a position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern
• activate the heater selectively.

A printhead maintenance module for a three-dimensional object printer comprising:

• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, each electric motor being operatively connected to one of the rollers in a one-to-one correspondence to enable independent and bidirectional rotation of each roller;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• and
• a controller operatively connected to each electric motor and the optical sensor in the sensor assembly, the controller being configured to:
• operate one of the electric motors to rotate at least one of the rollers to move media from a position opposite a printhead where a test pattern is printed on the media to a position opposite the optical sensor in the sensor assembly;
• operate the other electric motor to move the media between the position where the test pattern is printed and the position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern.

A printhead maintenance module for a three-dimensional object printer comprising:

• a frame;
• at least two rollers detachably mounted within the frame;
• at least two electric motors, the at least two electric motors being operatively connected to one of the rollers in a one-to-one correspondence and are configured to rotate each of the rollers independently and bidirectionally;
• a platen extending across the frame in a cross-process direction;
• a sensor assembly having an optical sensor configured to generate image data, the sensor assembly extending across the frame in the cross-process direction;
• and
• a controller operatively connected to each electric motor and the optical sensor in the sensor assembly, the controller being configured to:
• operate one of the electric motors to rotate at least one of the rollers to move media from a position opposite a printhead where a test pattern is printed on the media to a position opposite the optical sensor in the sensor assembly;
• receive image data of the printed test pattern generated by the optical sensor;
• and
• identify inoperative ejectors with reference to the image data of the test pattern.