| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a brake circuit for a motor which can quickly stop a motor in the case that a driven object runs over an emergency stop limit. <P>SOLUTION: Since the reversed input of an AND circuit 31 reaches an "L" level when a brake signal reaches an "H" level, the output of the AND circuit 31 reaches an "L" level. Consequently, an FET 35 is switched off, and the FET35 is switched off. Moreover, since the brake signal in one input of an OR circuit 33 is in the "H" level, an FET 36 is switched on. Consequently, the U-phase coil 23U, the V-phase coil 23V, and W-phase coil 23W of a three-phase linear motor 23 are short-circuited, and a dynamic brake works. Moreover, since the output of an inverter 37 reaches the "L" level, a transistor 38 is switched off, and the excitation of the coil of a relay 39 is lifted. Therefore, a relay contact 39b is switched off, and the U-phase coil 23U, the V-phase coil 23V, and the W-phase coil 23W of the three-phase linear motor 23 are short-circuited, and the dynamic brake works. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
