Serviceable sensor assembly and method

A sensor housing for a printer arranged to transport printed material along a path in a process direction, comprising:

• first and second ends;
• a first side rail segment connecting the first and second ends and including:
• a first top surface;
• a first bottom surface;
• and,
• a plurality of first resilient elements attached to the first top surface, each first resilient element located further from the first bottom surface than any first resilient element immediately preceding said each first resilient element in a direction from the first end toward the second end;
• a second side rail segment connecting the first and second ends and including:
• a second top surface;
• a second bottom surface;
• and,
• a plurality of second resilient elements attached to the second top surface, each second resilient element located further from the second bottom surface than any second resilient element immediately preceding said each second resilient element in a direction from the first end toward the second end, wherein the sensor housing is arranged to be disposed orthogonally above the path and house a plurality of light emitting elements.

A sensor assembly for a printer arranged to transport printed material along a path in a process direction, comprising:

• a longitudinal axis;
• a sensor housing including:
• first and second top surfaces;
• and,
• a plurality of resilient elements fixed to the first and second top surfaces;
• and,
• a platen assembly including:
• a platen housing with a plurality of steps;
• and,
• transparent material, wherein:
• the sensor housing is arranged to house a plurality of light emitting elements;
• the platen assembly is arranged to engage a first end of the sensor housing and displace in a first direction along the sensor housing toward a second end of the sensor housing such that the transparent material is aligned with the plurality of light emitting elements in a direction orthogonal to the longitudinal axis;
• and,
• as the platen assembly displaces in the first direction, the plurality of resilient elements is arranged to engage the plurality of steps to urge the piece of transparent material into contact with the sensor housing with progressively greater force such that the transparent material is sealed against the sensor housing.

A printer arranged to transport printed media along a plane in a process direction, comprising a sensor assembly, disposed above the plane in a transverse direction orthogonal to the process direction, including:

• a plurality of light emitting elements;
• a sensor housing with:
• a first sensor side rail including a first bottom surface and a first top surface forming a plurality of first steps, each first step with a thickness, with respect to the first bottom surface, greater than any first step immediately preceding said each first step in a first direction parallel to the traverse direction;
• a second sensor side rail including a second bottom surface and a second top surface forming a plurality of second steps, each second step with a thickness, with respect to the second bottom surface, greater than any second step immediately preceding said each second step in the first direction;
• and,
• a respective resilient element fixed to each first and second step;
• and,
• a platen assembly including:
• a platen housing engageable with and removable from the sensor housing in the traverse direction and including:
• a first platen side rail including a third top surface and a third bottom surface forming a plurality of third steps, each third step with a thickness, with respect to the third top surface, less than any third step immediately preceding said each third step in the first direction;
• a second platen side rail including a fourth top surface and a fourth bottom surface forming a plurality of fourth steps, each fourth step with a thickness, with respect to the fourth top surface, less than any fourth step immediately preceding said each fourth step in the first direction;
• and,
• transparent material fixed to the platen housing, wherein:
• when the platen housing is engaged the sensor housing and displaced a maximum distance in the first direction, the transparent material is between the plane and the light emitting elements and the respective resilient elements engage the pluralities of third and fourth steps to apply a first force to the platen housing to urge the transparent material into sealing contact with the sensor housing;
• and,
• when the platen housing is engaged with the sensor housing and displaced a distance in the first direction less than the maximum distance, the respective resilient elements are free of contact with the pluralities of third and fourth steps such that the transparent material is free of contact with the sensor housing.

A method of sealing a sensor assembly for a printer arranged to transport printed material along a path in a process direction, the sensor assembly including a sensor housing and a platen assembly, comprising:

• engaging a first end of a platen housing with a first end of the sensor housing;
• applying progressively greater force to the platen housing to urge transparent material fixedly connected to the platen housing into contact with the sensor housing by:
• displacing the platen housing a first distance in a first direction toward a second end of the sensor housing;
• and,
• displacing the first end of the platen housing an additional distance in the first direction, such that a plurality of resilient elements fixed to first and second top surfaces of the sensor housing engages a plurality of first steps of the platen housing;
• aligning the transparent material with a plurality of light emitting elements disposed in the sensor housing in a direction orthogonal to the first and second top surfaces;
• and,
• sealing the transparent material against the sensor housing.