Non-exciting shunting switch convenient for shifting

Abstract

The invention relates to a non-excitation tapping switch used for a transformer, which comprises columnar fixed contacts installed on the circumference and insulating terminal plates installed over and under the switch. A main shaft is installed between insulating terminal plates in a penetrating manner, and linked with an operating mechanism; and ring-shaped moving contacts are installed on the main shaft in a manner of bridge connection with two adjacent columnar fixed contacts. The switch is characterized in that a contact surface of a gear-shifting running track formed by the columnar fixed contacts corresponding to the moving contacts is a smooth transition curved surface. Through the scheme that the contact surface of the gear-shifting running track formed by the columnar fixed contacts corresponding to the moving contacts is the smooth transition curved surface, the invention reduces the crowning height of the gear shifting contact surface, shortens the retraction travel length of the gear shifting of the moving contacts, reduces the integrated torque of the switch operation, improves the stability of the moving contacts in running, and reduces the gear shifting abrasion of the fixed and the moving contacts. The invention maintains the advantages of stable contact and high reliability of the original contact structure, and can meet the demands that a plurality of parallel moving contacts are needed by multi-phase or strong-current single-phase switches.

Description

technical field [0001] The invention relates to an off-circuit tap changer for use in transformers. Background technique [0002] In Chinese patents CN1555070A, CN2454878Y, and CN2433720Y, several contact structures of non-excitation tap changers are disclosed. Between the fixed contacts, the contact surface corresponding to the shifting trajectory of the fixed contact and the moving contact is a cylindrical surface with the same center and radius. Running from one side to the other side requires a large radial stroke to compress the inner spring of the moving contact to reach another gear beyond the highest point of the static contact contacting the circular arc of the cylinder. The structure of this kind of contact is characterized by simple structure, automatic return, reliable contact, and strong hand feeling, but its disadvantage is that the excessive radial stroke will increase the operating torque, and the contact surface of the moving and fixed contacts will wear a ...

AI Technical Summary

Problems solved by technology

The structure of this kind of contact is characterized by simple structure, automatic return, reliable contact, and strong hand feeling, but its disadvantage is that the excessive radial stroke will increase the operating torque, and the contact surface of the moving and fixed contacts will wear a lot. The rigidity of the main shaft is high, and it is often difficult to realize or reduce the reliability of multi-phase or high-current single-phase switches with too many moving contacts in parallel.

Images