PURPOSE: To detect welding current irrespectively of whether it is AC or DC and to eliminate easily the influence of a high frequency component by disposing a magnetoelectric transducer within the magnetic field created by the welding current, and detecting indirectly the presence or absence of the welding current or the change thereof.
CONSTITUTION: When welding current (i) flows in a cable conductor, an alternating magnetic field for detection is applied on a magnetoelectric transducer 20. The transducer 20 induces a Hall voltage (v) corresponding to the alternating magnetic flux and inputs the same to an amplifier 30. When the output Qv of the amplifier 30 is larger than a set current value K, comparators 50A, 50B output respectively signals P1, P2 having a constant level. A discontinuous signal P is outputted from an adder 60, and the signal P is converted by a continuous signal M by an integrator 70. Said signal is transmitted to a relay driving part 80 and therefore the relay operates and the flow of the prescribed welding current (i) is detected.
SHINKAWA KATSUHIRO
FUJIMOTO KISHIO
| JPS5432540U | 1979-03-03 | |||
| JPS5432538U | 1979-03-03 | |||
| JPS54148638U | 1979-10-16 | |||
| JPS4725764A |