Friction attachment for a stencil to a rotary printing drum

A printer for printing out an image formed in a stencil on a sheet, comprising:

• a rotatable drum comprising a hollow cylindrical support having an apertured portion formed with a number of apertures, and a non-apertured portion, said apertured portion having leading and trailing ends with respect to a direction of rotation of the rotatable drum, wherein a stencil is wrapped around an outer periphery of said support such that leading and trailing edges of the stencil overlie parts of the non-apertured portion, with part of the stencil between the leading and trailing edges overlying the apertured portion;
• clamp means provided on said non-apertured portion of said cylindrical support for clamping the leading edge of the stencil wrapped around said support;
• ink supply roller means disposed in said support for supplying ink to said stencil via said apertured portion of said support;
• press roller means for pressing a sheet against said stencil;
• and
• friction generating means provided on an outer periphery of said drum for preventing said stencil wrapped around said drum from slipping out of said clamp means, said friction generating means including a surface providing increased frictional engagement of said stencil as compared with non-apertured portions not having the friction generating means thereon, at least part of said friction generating means located on said non-apertured portion of said drum at a location between the clamp means and the leading end of the apertured portion, such that movement of the stencil tending to cause the stencil to slip from the clamp means is reduced, and wherein a portion of the stencil extending from the trailing end of the apertured portion of the drum to the trailing edge of the stencil overlies the non-apertured portion and is not in engagement with the friction generating means.