| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent burning of components and to sustain press operation even if the stored energy is insufficient. <P>SOLUTION: The power supply of a press machine includes a power converter 30 (converter circuit 31) on the commercial AC power supply (10) side, and a power inverter 60 (inverter circuit 61) on the press motor (1) side, and is farther provided with an electric energy bank 50, a rush prevention circuit 24, rush prevention command signal generation means (71) and contactor switching means (73). On condition that a rush prevention command signal Sres is generated from the rush prevention command signal generation means (71) during press operation, the contactors 26R, 26S, 26T of the rush prevention circuit 24 are switched from ON state to OFF state, thus connecting rush prevention resistors 25R, 25S, 25T with the AC paths 11, 12, 13 of respective phases. <P>COPYRIGHT: (C)2013,JPO&INPIT |
