Abstract: A fly-back transformer to be used for use in the supply of a DC high voltage into a cathode-ray tube such as TV image receiving machine or the like. The ringing removing wire connected with the secondary winding through the distributed capacity with respect to the secondary winding to form a closed circuit of ringing current together with the secondary winding is connected in parallel to the primary winding through the DC resistance component, so that the ringing may be damped by the closed circuit.

Abstract: A flyback transformer comprising a primary winding wound onto a core, secondary windings wound in magnetic coupling with the primary windings, and diodes connected to the secondary windings respectively, each diode being mounted on the peripheral surface of a bobbin on which the secondary windings are wound and supported thereto through lead wires fitted into grooves provided at supports projecting from the peripheral surface of the bobbin, thereby simplifying the manner in which the diode is mounted to the bobbin and making it easier to automate both the diode mounting and the connecting of terminals of the secondary windings with the lead wires.

Abstract: An improved high voltage generating device such as a fly back transformer or the like which includes a first casing open at one side face thereof and accommodating therein high voltage electrical components, a second casing which is mounted in a cut-out portion formed in a side wall of the first casing and open at its one edge, and an electrically insulating material filled in a space within the first casing. In the above high voltage generating device, undesirable leakage of insulating material between a cut-out portion of a casing and a high voltage variable resistor during its injection into the casing is advantageously prevented without necessity for employing extra parts such as packings, etc., and thus the assembly work is simplified, with consequent reduction in cost.