| 摘要 |
<p>In a system for maintaining density of a printed color constant, a reading unit is connected with a unit measuring the reading signal. An amplitude measuring unit and a rated variable voltage source are connected with a comparator. The comparator is connected with a PID regulator, the signal of which is connected with a first adder which itself connects with a viscosity code setting potentiometer. The first adder is connected with a second adder connected to a viscosimeter. The signal produced by the second adder is sent to an amplifier connected with a command circuit for controlling mixer valves for ink and solvent. This command circuit can be locked or released by means of signals received from a level indicator in a tank. The command circuit also actuates a pump and a valve of a return circuit of the ink/solvent mixture. The system is employed for controlling and keeping constant color density of a print.</p> |
