| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact seal power control device, which is reduced in power loss and capable of accurately and stably controlling a heater under a feedback control.SOLUTION: A seal power control device is configured to control the power of a heater 5 provided in a sealer in a sealing section of a packaging machine. The seal power control device includes: a three-phase full-wave rectification circuit 11 with a smoothing capacitor to rectify a three-phase AC power source 10, which supplies power to the heater 5, to have a direct current; and a seal transformer 12 configured to supply the power rectified by the rectification circuit 11 to the heater 5. The state of the heater 5 on the secondary side of the seal transformer 12 is detected by a feedback circuit 14, and the DC power source rectified by the rectification circuit 11 is cut by a switching element Q1 in accordance with the value, and then, the pulse width of the DC power source to be supplied to the heater 5 is controlled. |
