| 摘要 |
Stencil cutting apparatus for electrically burning information from an original document into a stencil material having non-linear burning characteristics by the application of electrical pulses to a stylus contacting the stencil material positioned on a rotatable cylinder, includes a photomultiplier for scanning the original document and providing an output signal the amplitude of which is proportional to the light reflected by the information thereon, a circuit including a square wave oscillator and wave shaping network which alters the square wave in relation to the burning characteristics of the stencil material to produce a resultant train of pulses and a comparator circuit which adds the photomultiplier signal and train of pulses. The comparator provides output pulses having a width determined by the addition of the last-mentioned signal and pulses which are fed to the stylus for burning the stencil. The cylinder upon which the stencil material is mounted includes a magnet which revolves as the cylinder rotates. The movement of the magnet past a sensing coil produces a signal to discontinue the burning as the stylus passes over the stencil clamp of the cylinder. |
