INK JET APPARATUS AND CONTROL OF INK JET HEAD THEREFOR

摘要

PURPOSE:To reduce operation load with high accuracy by altering the drive conditions of an ink jet head on the basis of a specific number of numerical values corresponding to the accumulated quantity of heat of the ink jet head at predetermined time intervals. CONSTITUTION:The head temp. DELTATi by thermal time constant of the previous time obtained at Step S1000 is multiplied by a falling temp. constant at Step S1001 and the dots of an unit operation interval are counted at Step S1002 to obtain the given quantity DELTAQi of heat of the unit operation interval. Herein, the rising temp. component DELTAT of a head is determined by the pulse PWM control (Step S1009) used to head temp. due to environmental temp. A dot count is corrected by a drive pulse at Step S1003 and DELTAQi is obtained at Step S1004 by using an ejection duty/DELTAQi table. The operation value of the Step S1001 is added to DELTAQi at Step S1005 to obtain head temp. DELTATi by thermal time constant at Step S1006. This DELTATi is stored to be used in the next operation.