| 摘要 |
PURPOSE:To enable a rocking arm to have a large attenuation characteristic for bounding or vibration which is generated due to shock at the time of contact to be attenuated readily, in closing a main coil when a capillary contacts a pellet. CONSTITUTION:A drive circuit I 14 cuts off applied current to a main coil 41 of a moving coil 4 and applies current to a voltage-applied coil 42 only, thus enabling a capillary 3 to be driven at low speed until it contacts a pellet 9. When the capillary 3 contacts a pellet and output of a speed detector 7 reaches 0, a switching circuit 13 sets a switch 16 within the drive circuit I 14 to (b) side, thus enabling the main coil 41 to be short-circuited. At the same time, the switching circuit 13 selects a signal from a pressure command circuit 12 and applies a certain amount of current to the voltage-applied coil 42, thus enabling a certain amount of bonding pressure to be applied to the pellet 9. When the capillary 3 contacts the pellet 9, bounding or vibration easily occurs due to shock at the time of contact. However, the number of windings of the main coil 41 is large and a back electromotive force constant is large, thus enabling bounding or vibration to be attenuated readily. |
