DEVICE FOR SPRING CONTACT HARDENING Russian patent published in 2011 - IPC B21F35/00 F16F1/02 

FIELD: process engineering.

SUBSTANCE: invention relates to machine building and may be used for improving spring performances. Device comprises top and bottom inserts and barrel to accommodate said inserts and spring there between, punch with spherical surface in contact with that of top insert. Bottom insert is arranged to rotate about barrel axis and bottom insert may rotate and translate along barrel axis and deviate from punch axis. Inserts are provided with screw rectangular grooves on their face to feature diameter equal to that of spring ID and depth making at least spring coil diameter, coil rise being equal to spring coil diameter. Note also that barrel features inner diameter varying from contracted spring diameter to coiled spring diameter. Screw groove section may be made along spring coil radius and have depth making at least half the coil radius.

EFFECT: plastic hardening of springs with unfinished faces of extreme coils.

2 cl, 1 dwg