Abstract: An electronic stencil cutter having a rotatable drum with an original subject sheet and a stencil sheet mounted side by side thereon. Scanning and stencil cutting heads are mounted on a common carriage for simultaneous movement along the original and stencil sheets. The original subject sheet is retained in a holder consisting of a flexible, transparent sheet wrapped about the drum, one end of the retainer sheet being held releasably against the drum by a pressure-sensitive adhesive strip. The ends of the stencil sheet are held by an elongated clamp bar in a slot in the drum, the clamp bar being urged outwardly by springs and manually releasable by latch members at the ends of the bar. The stencil cutting head has a plastic stylus which is deflectible by a solenoid to press a wire electrode against the stencil sheet while cutting the stencil. The solenoid has a soft, felt-like nose which engages the stylus to dampen vibration of the electrode.

Abstract: An electronic stencil cutter having a rotatable drum with an original subject sheet and a stencil sheet mounted side by side thereon. Scanning and stencil cutting heads are mounted on a common carriage for simultaneous movement along the original and stencil sheets. The original subject sheet is retained in a holder consisting of a flexible, transparent sheet wrapped about the drum, one end of the retainer sheet being held releasably against the drum by a pressure-sensitive adhesive strip. The ends of the stencil sheet are held by an elongated clamp bar in a slot in the drum, the clamp bar being urged outwardly by springs and manually releasable by latch members at the ends of the bar. The stencil cutting head has a plastic stylus which is deflectible by a solenoid to press a wire electrode against the stencil sheet while cutting the stencil. The solenoid has a soft, felt-like nose which engages the stylus to dampen vibration of the electrode.

Abstract: A duplicating machine has an impression roll positioned to press copy sheets against a master sheet on a drum which is rotatable by an electric drive motor through a coil spring type clutch. The clutch consists of a coil spring having an interference fit with cylindrical friction surfaces on driving and driven clutch members which are connected respectively to the motor and drum. The coil spring is helically wound in a direction to tighten the interference fit when the motor rotates the driving clutch member to turn the drum in a printing direction; conversely, the interference fit loosens when the driving end of the coil spring is held, enabling the driving clutch member to rotate freely. A tang on the driving end of the spring is positively connected to a cylindrical release collar surrounding the spring. The driven end of the spring has a positive tang connection to the driven clutch member and drum.

Abstract: Duplicating machine having a drum rotatably mounted between a pair of side frames. Drum has a cylindrical wall having perforations communicating with an internal ink reservoir. An open mesh screen is stretched about the drum to provide an external cylindrical auxiliary reservoir immediately beneath an ink-distributing pad. Copy sheets are fed from a stack by adjustable pressure feed wheels and advanced along a path of movement to a first bight between a pair of forwarding rollers, and then to a second bight between an impression roll and the drum. Automatic apparatus is described for positively gripping a stencil sheet including provision for guiding the impression roll in non-interfering contact with the gripper assembly and for automatic alignment of the front edge of the stencil with the drum axis upon the positive clamping of the stencil sheet.