Abstract: For the purposes of removing a used stencil or an ink screen from the cylinder(s) of a duplicator, a rotatable core alongside the duplicator cylinder is driveable by a drive transmission from the main duplicator drive, by way of a freewheel clutch such that the core is driven only when the duplicator cylinder is rotated in the reverse direction as compared with the normal direction of rotation during printing, and also by way of a friction-slip connection arranged such that with no slip the peripheral speed of the core is higher than that of the duplicator cylinder along which it is mounted.

Abstract: A stencil duplicator has a rotatable support which, in use, supports a stencil, and a feed path along which a stencil is advanced as it is loaded onto the support defined by a supporting roller spaced from the rotatable support and a smoothly arcuate guide surface extending over a considerable part of the feed path between the roller and the support. The arrangement is such that as a stencil, whose trailing part is supported by the supporting roller, is wound onto the rotatable support, it is drawn over the guide surface.

Abstract: A sheet feed mechanism for feeding individual sheets from a stack thereof comprises a first generally horizontal surface for supporting the edge of a stack of sheets and a second surface for supporting a face of the stack, the second support surface being provided by a plate member supported above the first surface and inclined at an obtuse angle with respect thereto. The plate member is supported so that the second surface is urged towards the nip defined between the first support surface and a sheet feed roller in such a manner that as the second surface approaches the nip the obtuse angle increases. In a preferred embodiment a cam surface is provided on the plate member to adjust the rate at which the obtuse angle varies as the second surface approaches the nip. The preferred embodiment also includes means for adjusting the height of the nip defined between the sheet feed roller and the first support surface to permit feeding of different gauges of sheets.