| 摘要 |
PURPOSE:To allow the title device to detect wire disconnection and, at the same time, to discriminate short circuit of wire by inserting voltage dividing resistances in parallel with a ball formation circuit composed of a conductor connecting a high- voltage generating power source with a torch chip and another conductor connecting the power source with a wire and connecting a discrimination circuit to the voltage dividing sections of the voltage dividing resistances. CONSTITUTION:This wire disconnection detector is constituted in such a way that voltage dividing resistances 23 and 23 are inserted in parallel between a conductor 10 connecting a high-voltage generating power source 29 with a torch chip 8 and another conductor 11 connecting the power source 29 with the tail end 2b of a wire 2, and a divided voltage generated across the resistances 22 and 23 when a ball is formed at the front end 2a of the wire is discriminated by supplying the voltage to a discrimination circuit 24. When the wire 2 is disconnected or does not crop out from the front end of a capillary tube 4, the divided voltage generated across the resistances 22 and 23 becomes lower and, when the wire 2 comes into contact with the torch chip 8, the divided voltage becomes higher. By discriminating the divided voltage at the circuit 24, the occurrence of a disconnected wire and short-circuited wire can be recognized. |
