ON-LOAD TAP CHANGER

PROBLEM TO BE SOLVED: To provide a on-load tap changer which is compact, has high performance, can prevent a short-circuit accident from occurring by detecting an abnormality fast even in the case that a vacuum valve cannot be isolated and can achieve superior reliability thereby. SOLUTION: Peripheral sides of cams 27 composed of insulating materials are provided with grooves 27a and 27b and the grooves 27a and 27b and positions between main valves HA and HB and resistance valves WA and WB are provided with opening and closing mechanisms 30. The opening and closing mechanism 30 comprises driving bosses 20 connecting rollers 21 to the grooves 27a and 27b, opening and closing rods 24 connected to the main valves HA and HB and the resistance valves WA and WB each and wipe springs 25 provided between the opening and closing rods 24 and the driving bosses 20. Planar portions of the cams 27 are provided with long holes 27c. Auxiliary contacts KA and KB having contact rods 12 and contacts 15 are provided corresponding to the long holes 27c. COPYRIGHT: (C)2003,JPO