The inverter circuit can be structured by a simple structure as follows: an inductive element (the primary winding) 23 whose one end is connected to a DC power source 21; the first capacitor 24 connected in parallel with it; a serial circuit of the second switching element 27 and the second capacitor 25; a common connection point to which the primary winding 23, the first capacitor 24, and the other end of the serial circuit are connected; and the first switching element 26 to open and close control between the DC power source 21 and the other portion, are provided, and a drive signal generating means (resistance) is connected between the control terminal of the second switching element 27 and the common connection point.