Patent ID: 8119939
Filing Date: 2012-02-21
Classification: H01H

Abstract:
1. An on-load tap changer with an energy storage mechanism for uninterrupted changing over between different winding taps of a tapped transformer under load, the on-load tap changer comprising: a tubular dielectric cylinder having a wall and centered on an axis; fixed tap contacts in the wall; an axially extending switch column in the cylinder; drive means including a drive crank on the column for rotating the column; at least one switching element on the column engageable with the tap contacts; a support plate fixed in the cylinder; a spring tube pivoted on the support plate; a rod extending from the crank coaxially in the tube; a common spring abutment carried on the spring tube; an inner energy-storing compression spring between the rod and the tube, having one end bearing on the common spring abutment, and extending away from the crank; an outer energy-storing compression spring coaxially surrounding the tube, having one end bearing on the common spring abutment, and also extending away from the crank; a movable spring abutment on the rod against which another end of the inner spring bears; and a support pin projecting radially outward through the tube from the movable spring abutment and against which another end of the outer spring bears.