Moistener preparation system for offset printing - has reservoir which can be supplied with water and alcohol, with additive and amount of water flowing measured by water meter depending on filling level position

摘要

The alcohol and additive amounts are dosed by respectively assigned pumps (21, 22). The additive dosing pump (22) at least, is connectable to an exchangeable drum (17a), and can be activated proportionally to the amount of water fed in to the reservoir (1). A control unit (25) is provided, by which, during an exchange of a drum, a medium amount value to be dosed, depending on the amount of running water fed in to the reservoir, is storable. The dosing pump (22) assigned to the relevant medium is activated depending on the amount value stored by means of the control unit, after the resulting drum change. The additive dosing pump (22) is controlled (25) depending on the amount value stored. With the exhaustion of the drum (17a) assigned to the medium to be dosed proportional to the amount of running water, signals are produced after a drum exchange, which are activated by the assigned dosing pump (22), which respectively carries out a test stroke at intervals. An alarm signal is activated with empty drum. ADVANTAGE - System is improved by simple and cost effective means, so that operation is made easier, yet high accuracy is attained.