Binary ink developer assembly including a guard member including a conforming end having a concave shape

A method of operating a binary ink developer (BID) assembly, the method comprising:

• receiving ink by a developer roller of the BID assembly;
• rotating a squeegee roller having a curved circumference forming a second arc to regulate a film thickness of the ink on the developer roller as the developer roller rotates;
• transferring a portion of the ink from the developer roller to a photoconductive member;
• and
• reducing an amount of ink unintentionally exiting a housing of the BID assembly by a conforming end of a non-electrically conductive guard member of the BID assembly having a concave shape forming a first arc corresponding to a portion of the curved circumference of the squeegee roller such that the first arc and the second arc are concentric arcs, wherein a space formed between the first arc of the conforming end of the guard member and the second arc of the curved circumference of the squeegee roller is located between the housing and the developer roller, a first region on a first side of the guard member located between the housing and the conforming end, and a second region on a second side of the guard member located between the conforming end and the developer roller, and the space extending between the first region and the second region,
• wherein the squeegee roller rotates in a direction to viscously pump ink towards the second region.

A binary ink developer assembly usable with a printing system, the binary ink developer assembly comprising:

• a housing;
• a developer roller to receive ink and transfer a portion of the ink to a photoconductive member;
• a squeegee roller to rotate and regulate a film thickness of ink on the developer roller as the developer roller rotates, the squeegee roller including a curved circumference;
• and
• a non-electrically conductive guard member including a conforming end disposed across from the squeegee roller, the conforming end having a concave shape corresponding to a portion of the curved circumference of the squeegee roller, wherein a space formed between the conforming end having the concave shape and the portion of the curved circumference of the squeegee roller directly across the conforming end is located between the housing and the developer roller, a first region on a first side of the guard member located between the housing and the conforming end, and a second region on a second side of the guard member located between the conforming end and the developer roller, the space extending between the first region and the second region,
• the squeegee roller to rotate in a direction to keep ink in the second region and away from the first region.