Selector switch assembly for load tap changer

A selector switch assembly for load tap changer of a transformer having a plurality of phase windings, the assembly comprising:

• a bevel gear structure coupled with a motor drive shaft,
• a shaft assembly coupled with the bevel gear structure so that the bevel gear structure causes rotation of the shaft assembly, and
• a switch for each of the phase windings, each switch comprising:
• a helical gear fixed to the shaft assembly for rotation therewith,
• a pinion gear directly engaged with the helical gear so as to cause rotation of the pinion gear, the pinion gear having a first follower coupled to one side thereof and a second follower coupled to an opposing side thereof, the pinion gear having a hub,
• a first Geneva gear wheel mounted on a first shaft and associated with the first follower,
• a second Geneva gear wheel mounted on a second shaft that is concentric with the first shaft and associated with the second of the follower, each of the first and second Geneva gear wheels having a plurality of spaced slots in a periphery thereof such that when the pinion gear rotates and the associated follower engages a slot, the associated Geneva gear wheel rotates an intermittent indexed amount,
• a first contact arm associated with the first Geneva gear wheel so as to rotate therewith, and
• a second contact arm associated with the second Geneva gear wheel so as to rotate therewith,
• each of the first and second contact arms having contacts constructed and arranged so that upon rotation of the contact arm, the contacts engage fixed contacts which define tap positions of the load tap changer.