Numbering unit in typographical set on printing machine - has monitoring numerator producing error signals for unmatched discs

摘要

The numbering unit is designed for incorporation in the typographical set on a printing machine. It is monitored by a numerator which can produce error signals. Each disc (102) of the monitoring numerator has the same number of halting positions as the corresponding disc on the numbering unit being monitored. Each such position corresponds to a location unit which produces a signal. The signals belonging to the two discs are combined. All the signal information from the discs is reorganised to produce an error signal if one disc or more in the monitored numerator is ina different position from the corresponding disc on the monitoring numerator.