Apparatus and method for image production device media hold down transport air flow

A method in an image production machine including a media transport belt configured to transport media sheets in a process direction, the media transport belt including a plurality of belt apertures arranged along a cross-process direction, the cross-process direction perpendicular to the process direction, the image production machine including a vacuum plenum assembly, the vacuum plenum assembly including a plurality of plenum apertures arranged along the cross-process direction, the method comprising:

• transporting media sheets in the process direction by moving the media transport belt around the vacuum plenum assembly;
• shifting a relative position between the media transport belt and the vacuum plenum assembly in the cross-process direction to change an alignment between at least some of the plurality of belt apertures and at least some of the plurality of plenum apertures;
• and
• conducting pressurized airflow via at least some of the plurality of belt apertures and some of the plenum apertures to secure the media sheets on the media transport belt.

An image production machine comprising:

• a media transport belt configured to transport media sheets in a process direction in an image production machine, the media transport belt including a plurality of belt apertures arranged along a cross-process direction, the cross-process direction perpendicular to the process direction, the plurality of belt apertures configured to conduct air to secure the media sheets on the media transport belt;
• a vacuum plenum assembly, where the media transport belt moves around the vacuum plenum assembly, the vacuum plenum assembly including a plurality of plenum apertures arranged along the cross-process direction, the plurality of plenum apertures configured to conduct air, the plurality of plenum apertures including at least a first plenum aperture of a first width in the cross-process direction and at least a second plenum aperture of a second width in the cross-process direction, the first width different from the second width, the vacuum plenum assembly including a vacuum plenum assembly center in the cross-process direction where the first plenum aperture is distal to the vacuum plenum assembly center in at least one direction from the vacuum plenum assembly center relative to the second plenum aperture, and where the first width of the first plenum aperture is narrower than the second width of the second plenum aperture;
• and
• a media transport shift assembly configured to shift a relative position between the media transport belt and the vacuum plenum assembly in the cross-process direction to close least a first of the plurality of belt apertures by shifting the first of the plurality of belt apertures away from the first plenum aperture.