Document belt vacuum manifold

In a document handling system in which documents are moved with a vacuum belt to an imaging station of a copier where the document are illuminated for imaging against a light reflective document imaging surface on a first side of said belt with a width greater than that of the document, and in which document handling system the documents are vacuum attracted toward said first side of said belt by an air flow applied from vacuum apertures in a light reflective vacuum manifold surface at the backside of said belt, which vacuum air flow is communicated from said manifold apertures through further apertures in said vacuum belt which open on said first side of said belt, the improvement wherein:

• said vacuum manifold surface at said backside of said belt has elongated grooves slightly recessed in said manifold surface,
• said manifold surface grooves extend in the direction of movement of said belt spaced apart transverse the direction of movement of said belt, and relatively narrow in comparison to the overall width of said vacuum belt,
• said vacuum apertures in said vacuum manifold surface open recessed within said grooves in said vacuum manifold surface;
• said vacuum belt apertures are in narrow bands of apertures similarly transversely spaced apart and similarly extending in the direction of movement of said belt to generally overlie said grooves in said vacuum manifold surface,
• said manifold surface grooves have a sufficiently large cross-sectional area to provide relatively unrestricted air flow from said manifold surface apertures along said grooves under said belt to said vacuum belt apertures.