Stackable printer module for effecting double-sided printing

1. A printer module comprising:

a housing surrounding a frame and defining footing holes;

a print engine housed within the housing, and having a pair of opposed print head assemblies for enabling double-sided printing on print media to be effected; and

feet extending from the housing and spaced apart to engage in respective footing holes defined in the housing of another printer module so that the printer modules can be stacked together.

2. A printer module as claimed in claim 1 , wherein each foot has a bayonet fitting so that, when the foot is inserted into a corresponding hole, the foot can be turned to lock the foot in the hole.

3. A printer module as claimed in claim 2 , wherein each foot can be turned a quarter of a turn.

4. A printer module as claimed in claim 1 , wherein the housing comprises a pair of opposite covers interconnected by a pair of opposed side walls.

5. A printer module as claimed in claim 4 , wherein each side wall terminates in an end cap or cheek molding.

6. A printer module as claimed in claim 1 , wherein the footing holes are arranged to form a plurality of spaced apart sets with each set comprising a row of spaced apart footing holes.

7. A printer module as claimed in claim 1 , wherein the housing is elongate and defines print media entry and exit slots at respective ends through which the print media can pass.

8. A printer system comprising a plurality of printer modules as claimed in claim 1 and which are stacked together to form a diagonally or a vertically extending tower.