DEVICE FOR SPRING CONTACT HARDENING Russian patent published in 2013 - IPC B21F35/00 B26F1/06 

FIELD: process engineering.

SUBSTANCE: invention relates to machine building and may be used in production and application of springs at industrial enterprises. Proposed device comprises top and bottom inserts, barrel to accommodate said inserts and tested spring, and punch with spherical surface to get in contact with that of top insert. Bottom insert is fitted to rotate about barrel axis while top insert rotates and displaces relative to barrel axis and deflects from punch axis. Said inserts have circular grooves at their ends. Diameter of said grooves equals spring ID while groove depth makes, at least, spring turn height. Barrel ID varies from contracted spring diameter to coiled spring diameter. Top insert and punch are coupled by stepped screw with provision of clearance between screw body outer surface and that of holes in inserts and between screw head and insert mating surface.

EFFECT: higher efficiency of spring hardening.